There's a lot to consider here.
If you don't see yourself making use of the points for travel, then don't bother with the charge cards. Cash value on MR points is pretty crap (0.6 cents per point). The best way to get value from them is to transfer to partner airlines.
intermediate level hack: You CAN get decent cash value from MR points (1.25 cents per point) if you have a Schwab Platinum card, but then you're paying the Platinum annual fee. If the Platinum card benefits are worth the fee for you then this may be an OK way to cash out points. Otherwise just stick to airline transfers as mentioned above.
Another probably more relevant tip: You CAN transfer MR points to British Airways and redeem for AA flights.
Charge cards cannot be downgraded to no-fee cards. You can downgrade the gold to the green, but you'll still have a $150 annual fee on the green.
If you'd rather avoid the work of figuring out points strategy, the flexibility of cash back makes more sense for you, and you don't travel much anyway, I'd recommend you go with one of the cash back cards (BCE, BCP, or Cash Magnet).
I agree with @MrDisco99 that my first inclination is that the cash back cards might be a better fit for you, @aleacosta5.
I was going to ask the "Do you travel?" question as I was reading but you eventually discussed it.
My other questions are:
- What areas do you normally spend the most on monthly?
- What other rewards credit cards do you already have? (i.e., how would this fit into an overall lineup?)
I usually discourage members from SUB-chasing but that's my preference. Most times, I try to pick cards that I plan to keep and the SUB is just the icing on the cake. There are those who do it often but it can come back to bite you when lender see the carnage on your report. AMEX recently told me if I completed an app for a Hilton card for which I was preapproved that I wasn't eligible for the SUB due to my overall open/closed accounts and SUBS, and I don't consider myself a SUB-chaser.
The word-on-the-street is that with AMEX, the easiest cards to get are the cobranded revolvers like Hilton, Marriott or Delta. Then the charge cards (Platinum, Gold, Green.) The most difficult are the core revolvers like the Cash Magnet or Blue Cash Everyday/Preferred.
Even if you travel only once or twice a year, it could easily be worth your while to collect MRs for those trips. As long as you don't mind deferring the cash back and you travel SOME, it deserves a consideration. You don't have to be a hard-core road warrior to benefit from travel points. But the other part of the travel question is, when you do travel, what does it look like? Do you fly or drive? Domestic or International destinations? First Class, Business or Coach? Do you treat yourself to premium hotels or prefer budget chains? The more expensive your travels (airfare, hotels, length of trips, etc.) the more likely that travel points could be beneficial. On the other hand, if you fly the ultra-low cost carriers like Spirit or stay in a local hotel after driving to a domestic beach, you may be better off with cash back.
The Gold card is a great charge card. There is an opportunity to offset almost if not all of the $250 Annual Fee if your lifestyle is a fit. Plus the SUBs are indeed better on the charge cards, but I wouldn't get one just for the SUB. There is a $120 credit for UBER or UBER EATS. And a separate $120 credit for selected Dining to include Grubhub delivery. And there is a $100 credit if you splurge on dining or spa expenses with a hotel in their Hotel Collection. Everyone eats, and the 4x MRs the Gold card earns on both dining out or supermarkets can be very valuable. Not for cash, though. The points cash out at 0.6 ccp so that's only a 2.4% return if you want cash. For gift cards or travel, and especially if you learn to leverage the points by transfer to travel partners, each point can be worth 1-2 ccp, so that gives you a 4% to 8% return on dining and groceries. And the $25K annual grocery cap is much higher than Blue Cash Preferred's $6K. The gold card comes with some nice additional benefits that some other cards have nerfed like Purchase protection, Extended Warranty coverage, Trip delay and Baggage insurance. If you travel internationally, there's no Foreign Transaction Fee and you have access to the Global Assist Hotline. Not to mention that it's a cool premium metal card. 
But if you don't plan to keep it for at least a couple of years to give it a fair test-drive, I think I would suggest a no-AF cash back card instead.
No, there's no downgrade to a no-AF version of the charge cards. You could get the Gold and downgrade to the Green, but you'd still have a $150 AF. And the credits (primarily the airport CLEAR security screening the airport LOUNGE BUDDY) might be less useful to you that UBER/Grubhub. The Green card earns well on dining out, transit, and travel but if you can't take advantage of those credits, you may be able to find a better dining-travel card.
If you don't already have a card that earns at least 1.5% or more, Cash Magnet can be fine for uncategorized spend. But there are TONS of 1.5% cards and also many 2% or better cards. Personally, I wouldn't waste time with that if you could get a 2%+ card. If you don't already have a card earning 3% on groceries, the Blue Cash Everyday might be a better choice.
Can you make use of the multiplier categories on the charge cards? If not, is it worth the hassle? Minimum spend with sub on the gold when redeemed for cash comes to $474 minus $250 for the AF leaving you $224. Green is $282 - 150 = $132. Since Amex doesn't like sub chasers, you would have to keep the cards for at least 1 year, if not 2, to make sure they don't blacklist you from future subs.
I could use the points for travel, but just once or twice a year. I always try to travel on a yearly basis (don't mention 2020 please), which means I won't take full advantage of the Platinum Card. I like your MR points trick with British -> AA.
About the Cash Back options, I really like the Cash Magnet, but I'm not sure if pointing to the Citi DC can be a better option in the future (1.5% vs 2%). The BCP/BCE options are good, but my purchases are mostly from BJ's / Costco which aren't considered for the 3/6% Supermarkets Cash Back. The same with the gas stations... so I will mostly get 1% back from my purchases, making the Cash Magnet a better fit for me between the three cash back options..
Do you think it's worth keeping the Green / Gold long term for a casual traveler? I am fine paying an annual fee if I'm going to take advantage of the points.
What I like the most about the Gold Card:
- 4x at restaurants
- 3x on flight bookings
- Uber credits
- Dining credits
About the Green:
- 3x at restaurants (Still acceptable for me)
- 3x on transit / travel (It doesn't have Uber credits, but at least it gives me 3x)
- Lounge access credits (The gold card doesn't have this, right?)
Btw, awesome feedback! Thank you!
Areas where I do spend the most:
- Restaurants
- Online stores (As Amazon, Apple, Microsoft, etc)
I just have a Citi Rewards+ card at the moment. I'm thinking about collecting MRs for my trips. As you say, it's not only the airfare.. I tend to rent a car + restaurant expenses, hotel sometimes, etc. The no Foreign Transaction Fee is a big deal while traveling (My Rewards+ has FTF) .
I don't fly the ultra-low carriers; deciding between Economy, Business or First Class mostly depend on the cost (sometimes is affordable, sometimes is just ridiculous), but if I can do it, I'll pick the better option for me. I also like to go to lounges while traveling.
I thought I had to be a frequent traveler to take advantage of the charge cards perks, thanks for clarifying!
I'm not trying to do a SUB-chase, but if I can pick a good offer on a card that it's worth keeping long term, I'll do it. I also thought AmEx only gives you a SUB once in a lifetime.
As @MrDisco99 said, I think the best use for me is by playing around with travel partners to take advantage of the points I can collect. I'm completely open to go through that path. Also, your whole explanation is making me really curious to give it a try for a couple years lol 
Worst case scenario, I will downgrade it to the Green and see what's better for me.
I'm currently between Gold and Green... I'll take another look at both cards and call AmEx tomorrow if possible.
Do you know if having an AmEx from another country is a plus? I have a Platinum credit card + a Gold charge card (not the same perks as the US options it's completely different....)
Thanks for the whole advice! I appreciate it.
@Brian_Earl_Spilner I think I can make use of the multiplier categories. Restaurants, flight bookings and transit to be specific.
@FormerCollegeDJ I still think the Citi DC could be a better option (When thinking about the Custom Cash). Most part of the purchases I do don't belong to the 5% category.
Thanks everyone!
I'd call myself a casual traveller in that I don't do much travel for work and my wife and I will do a few road trips per year and a big fun overseass trip every few years.
For me the Gold card works because of the high point earning on restaurants and groceries, which are two high spend categories. I don't travel often, but when I do I like to do it for free. Of course that means I spend a lot of time collecting points without actually using them. This can be risky from an inflation perspective. Amex can devalue those points whenever they want. Something to keep in mind as a risk.
Thanks to 2020 I now have a pretty big stock of Amex points which I intend to use on something big hopefully next year.
Update:
I finally applied for the BCP. Here is the approval link.
Since the Green/Gold charge cards don't have a $0 intro AF, I decided to pick the BCP since it can give me more time to evaluate my spending behavior and think if the charge cards can be a good fit for me in the future.
The BCP has a $0 intro AF, so basically I have 2 years to give it a try and see what happens (I'll probably keep it long term). I also didn't know the "6% CB trick" on supermarkets by purchasing gift cards to take advantage of the 6%. It has a nice SUB too.
Thanks everyone for your help and patience