1) I think Larian hopes to put in a system to let you change the default classes of OTHER companions when you recruit them, so you can pick what you want and change them to fit the party.
2) You just complained about discovering that your other party members are the same archtype as you are, now you're saying that you hate the idea of respeccing them? Sorry, but in my view, even if it hurts your immersion briefly, a companion respec-on-recruitment is a better way to handle it than setting a default for the origin characters and discourage you from making your main character what you want it to be.
4) Larian could make those objects worth 0 gold, but really, if you're going around picking up and selling every single junk item worth 1 gold, the only one you're hurting is yourself.
If you really want to see a strange quirk with the scarcity, get someone with Telekinesis into the fort, and you can find 700 gold worth of free and totally unguarded (if sneaking) paintings. I'll also note that it really seems like selling the paintings and equipping yourself with better gears and skills is required to be able to handle the absolutely brutal level 4 enemies.
I totally agree with you that selling huge paintings to prisoners in rotten tents does not work as a sensible source of gold income, and I'd rather have the gold amount directly placed somewhere. Small quests to earn gold are also a good idea.
5) Perhaps once you get off the island, skills will require several more points in the respective schools to learn. At least that seems like a good idea for balance. The low level skills on Fort Joy can be used with only a point or two, but the better ones need heavier investment.
6) Yeah, Earth is another pretty strange skill. I hate the change to remove Earth damage from wands/staves and replace it with poison which undead are immune to (and which spreads like crazy). The way it's split between Earth and Poison is a bit strange and unfocused, and it makes Earth resistance seem poor. I'd like more Earth damage skills too.
7) Agreed on all points.
8) Even after all this time, I still haven't made up my mind about the armor system. It has some good points and bad points, and I don't have any ideas about how I would change it, even though I definitely do not entirely like the system.
10) Agreed.