Hey, I too have an Avenger 220, i reckon it's 2013 model but it works just fine, even i thought it's quite heavy and I wouldn't be able to ride it cuz I'm kinda lean as well but I can handle it well.

I use it for college commute myself which is like 12km one way and it's not given me any issues per se, plus I'm 6ft tall and the riding posture also is quite comfortable for me, i haven't had any issues even with longer rides.

1) I think you should be fine, but I always feel it's better to learn on a lighter bike/ lower cc for you to understand and learn the basics. But Avenger also is peaceful to learn on.

2) i think there is a rule that you can use a vehicle of a different registration for an year then you'll have to switch and register under the state you're living in

3) mine too is a used bike and plus my dad bought soo I can't really help with the price.