1/ You really get shafted on slave prices. Maybe there's a tax on slave sales? That, or the slave traders are making huge profits.
2/ Don't like the trading of slaves for attributes either, but it does explain why everyone isn't walking around with 6s in every attribute.
3/ Obedience has gone through a lot of changes. I agree that as it stands, it doesn't matter much, and is only an issue early game. More obedience uses might just lead to a lot of micro managing, though.
4/ Mithril isn't really a late game resource, more of a mid-game one; and it takes a long time to mine enough for all tools, weapons and armors, so it's not really an issue to be available early on, but maybe locking villages until a few quests are done early game would make steel more relevant.
Screw bones though, who ever heard of bone tools past the ancient era?
5/ Days used to be 24 turns long. It was kind of micro manage-y, so 4 turns is a reasonable compromise. Things go pretty fast sometimes.
6/ Should you be able to see race-specific classes, or unique classes from unique characters?
7/ Agree on everything there. And more quest variety wouldn't hurt.