Do you plan on flying Delta? If you can make use of the free perks it could be worth it to keep even with a low CL, but that's for you to decide.
@Anonymous wrote:
I fly delta about twice a year. That does make sense.
There ya go... with two round-trips you'll earn back the AF via baggage waivers with some change to spare... don't forget the other Delta perks as well!
I do 'feel your pain', though... I also have a Delta Gold with a $1k credit line, and in my own case I suspect they won't be giving me a CLI either (based on history from 16 years ago with them). My plan is to go ahead and pay the AF the first year - even if I never fly Delta - and continue to use it for the Amex offers. They are rather 'hit and miss', but when the really good ones come around it can be lucrative to have an extra Amex in the wallet. 
Also don't forget the $50 statement credit for making a Delta purchase the first three months the account is open. It's not guaranteed, but many people have been able to trigger this by purchasing a Delta gift card from the Delta website (google for details). Again, YMMV, but it has worked for many people, and in the event that it doesn't work you'll just have a gift card to put toward your next flight... no harm done. 
I questioned if I was going to keep my Delta Gold as well. Mine is also at a 1k limit, but the waived baggage fees is one of the reasons I've yet to get rid of it. I had originally got it for the bonus, and decided to make it even more worth while by flying Delta whenever possible. I've flown Delta twice since I've got it in March and that has saved me, my wife, and family a total in $350 in baggage fees. I have two more delta flights in Sep/Nov which will net me another $200 as well. Combine that with the priority on getting on the plane and the small discount and it's already worth it. I've even set my Amex Platinum $200 waiver fee to Delta, so I have almost nothing to worry about when it comes to flying with them at the moment.
Also, I've spent over the 1k credit line for plane tickets a few times already so the credit limit has yet to hurt me any way yet (of course I pay it off immediately).
On top of that, since AmEx Platinum forces SPG Gold, I get SPG points for flying Delta via Delta Crossover rewards. I also rent my cars through Enterprise on the Delta website using my Enterprise membership number so I'm getting an over abundance of Skymiles, SPG points, and Enterprise points. Hopefully you can squeeze some more stuff out of the card... at least until the AF as Uncle B mentioned!
@Anonymous wrote:
I fly delta about twice a year. That does make sense.
As UncleB says, the two round trips alone handle the AF. You remember checked bag fees? Since I've had my Delta card, no checked fees on Delta, so when Jet Blue tagged me for a $25 fee coming out of BOS I was like, "Seriously?".
The other thing you may not have experienced yet is getting Group 1 boarding, ahead of the cattle-call Group 2 boarding. It's a little thing, but wow is that nice.
The thought of keeping it open makes sense to me. Being that it's fairly new and may still grow, as well as you might still fly a couple of times, it may be worth holding on to. I can understand your initial thoughts on closing it though.
