Well this would be my area of expertise...
After you get your rating in the ANG, you can get an FAA job. I (and 5 other trainees I was in training with) was applying for this job while I was still in training. You definitely don't have to wait until your contract is up. I still have 3 years left on my contract and there are numerous FAA controllers in my guard unit.
Not all VRA's get the 20K bonus (I didn't, nor did anyone in my unit so far and we have had 5 people hired onto the FAA in the last year). There are a lot of stipulations that go into that.
Vengeance, you could join any day you want to. We had three 19 yr olds training with me.
You will still have to go through OKC academy, no matter if you get hired center, tower, or terminal. But you get to skip basics, and yes, you do get about double the pay of the CTI and OTS peeps.
Let me know if you guys have any questions.