1) I painted my first car using a BC/CC Urethane system at my house and friends of mine who have re-finished cars for years said it looked great, except for my crappy body work. It is that easy to use.
It is also as environmentally friendly as automotive paints get. That is to say no automotive re-finish paint is going to be, well Green, for lack of a better term. Which is why they are meant to be applied in a controlled environment (read paint booth).
Think about it, if Lacquer based paints were so good and eco friendly why did the industry move away from them?
It's just as easy to repair a mistake in a BC/CC system as it would be with Lacquer. You can sand defects in the base and either re-apply more or depending on the mistake just proceed to the Clear Coat (after cleaning appropriately).
In fact I think almost every one makes mistakes when painting regardless of the type. Knowing how to take care of it is what matters, along with how to prevent it from happening again
2) This makes no sense. You can wetsand and buff just about any type of automotive paint.
3) No it won't? Who told you that? Look around these and other forums at people who've painted their own cars.
4) That's a good work ethic to have.
5) From what I've read and heard, acrylic enamel is very difficult for first timers to spray and needs to be done in a controlled environment. Someone may correct me though.
If you can tell me/us why you can't shoot urethane where you live then maybe it help to understand.
Personally I think your making too much of this (I mean no offense). No matter which type of paint you choose to use your going to have environmental issues to overcome when working out of your garage.
No matter what paint type you chose to use your also going to have issues that may need to be addressed. Automotive re-finishing while not rocket science, is a little complicated at first. Till you learn about it.
Thoughts and comments expressed by me are mine based on my own experience and research and shared here freely. I am not a professional nor make any claim to be as such