Yes, paintings should be worth much less. A tenth of their current price, I say. Same with cups and forks and stuff. Really, they should make everything the player sells worth less, because as is, getting money is absurdly easy. It could be part of the difficulty scaling: the harder the difficulty, the less you sell your stuff for. Easy: what you sell stuff for now, Medium: 75% value, Hard: 50% value, Hardcore (new difficulty), 25-30% of current prices (might be a little too low at that point, but it probably would still be plenty.

Actually am working on a post about suggestions regarding loot and economy, so glad to see Larian realizes at least paintings are an issue.

It'd be cool if stealing in general had more consequences, and preferably delayed ones. What if it affected your reputation? I mean, if the whole town has all their belongings stolen right after you showed up, I think people would at least trust you a little less.

Only being able to sell stolen goods to a fence would be cool too, but that's probably too much to ask.