Alltel level-7 tech support won't have a clue what is going on. Imagine you installed Linux on your phone .. would you still expect Alltel to support it? Save yourself the hassle and flash back to stock. It takes less time than you will sit on hold, and you are more likely to get the answer you are looking for.
The reason "official" ROMs are few and far between is because the release must be supported. It requires extensive testing. One overlooked issue can run up millions in damages (fruitless support calls, lost customers, negative brand image, etc). Look around at the latest test release .. some people have no problems, while others are borking their phones. Even 1% failure is not acceptable, so the release is held back until it will work for everyone.
BTW, you pay Alltel money each month for the service, not the phone.
It is in Alltel's best interest to ensure the phone works as expected with the service, so the phones (hardware & software) they provide are tested and supported. However, if you change the phone (unless instructed to by Alltel or the device manufacturer) the warranty is invalidated.
I used to work in tech support for Sprint years ago, and trust me it was much more fun to talk to Grandma than the guy that thinks he knows it all.