Any postive steps you take on trying to pick up your score are good steps, and yes, they will ultimately get you where you want to be. You're lowering your utilities, which is a big deal. Your FICO score is heavily impacted by your utilizations, so good job there!
Now it's a little iffy to depend on those "mail offers." Most people will tell you that that is just direct marketing and they got your name somehow and want you to apply. At this point, they really have no clue as to what your score is or who you are. I remember how excited I was when I received one of those for Discover card about 2 years ago. I went and applied, and was D-E-N-I-E-D....instantly! LOL! That's when I learned my lesson that you have to do your homework and find what the CCC's want from you! For example, I checked a thread that was entitled "Bankrupt Friendly Credit Cards" in the Credit Card forum, and found out about a couple of cards like who they pull from, and what scores are needed. I have never had a BK, but thought that I could have a shot at a couple, and to my surprise I got approved on the Carnival Sea Miles and Hooters Card.
You sound like me when it comes to holding off to see if you will be rewarded for all the hard work you've put towards building your credit! I hope when you go check it on September 15, you will see those scores go through the roof! Although I am so far from being a credit expert, my advice is to do your research on credit cards and then you choose who has the priviledge of offering YOU credit and getting your business! GOOD LUCK!