People that want Boston will get Boston, unless another base opens and they have to put people there (possibly Cincinnati). Right now, they are a little short of FOs in BIL but not short Captains. Some FOs are spending up to a bid period in BIL but, as other classes get out of IOE, they are going to BOS. Right now, almost all captains are going to BOS (very few aren't) and it looks like they are needing about 4 more FOs in BIL, so you get a choice until those are filled, but most are choosing BOS. You won't get stuck out west for more than a month if you don't want to be there.
As far as commuting, you could commute from almost anywhere if you get a crash pad. I know that there are people commuting from a few places, including Seattle. Just look and see what options you have for flights. There is currently no commuter clause in the contract, but the new contract, if it happens, should have one. Also, no CASS, but rumor has it that it should happen in the next few months (but they have been saying that for a few months).
If you are close to having the hours, apply online every two weeks. Sometimes it takes a few times to get Stig's attention.