Reasonable advice. I guess I just don't have the time or the patience for wikidrama and ArbCom cases seem like they would be too much effort. Clearly I am far too apathetic about WP to ever get banned in the first place :P I've seen quite a few people like that though - newbies who come to WP with something to contribute, get blocked for NPA when someone bites them for not filling in form 2451x.2b correctly, and leave in disgust, confused about the whole thing and lacking the motivation to bother getting unblocked. This isn't very widespread, but it does happen.
You're right, that certainly does happen. Reducing the bureaucracy would be good, but I'm not really sure how to do it without significantly increasing admin/arbitrator workload (and therefore, backlogs).
That said, I don't think it's a particularly big deal. If you're getting banned in the first place you're probably enough of a disruptive element that it's better for you to (a) leave or (b) get a new account and edit non-disruptively without the shadow of all the drama over you.
In most cases, yes. There are a few cases where something needs to be done, but the community don't like it, and whoever is finally bold enough to just go against consensus and do it (using IAR, I guess) ends up getting in trouble for it. It doesn't happen very often, but it does happen, and we really don't want to lose those people.