ColonelMace
Novice
It doesn't really add difficulty to the exprience anyway. PotD does that more effectively.This means that if you are autistic enough you can just save, turn it off, check out all you need, and reload to have it back on and still get the achievement at the end.
Expert mode is like Hardcore mode in New Vegas : it adds more or less tedious factors to make the player think a little bit more about what he's doing.
But it's still not all that impactful. The only parameter that I found made an actual difference was hiding the AoEs when casting fireballs and such friendly fire sensitive abilities. (Without mentioning how it makes it all reminiscent of the IE games as well).
Another aspect that, this time, mattered little in my memories was the restriction to accessing the party's chest.
If i'm not mistaken, you could exploit the UI to transfer stuff from the chest to the characters' inventories. Although it's probably been fixed.
The single most excellent aspect of expert mode, though, is hiding all the dialog tags from the player (regarding skills, background, reputations etc).
It makes the whole game more organic on this front, which cruelly suffers from purple prose and lack of personality for most npcs.
This, however, turns into a severe flaw when playing either a Paladin or a Priest, who benefit or suffer from whatever reputations they earn during the journey. Simply because it's more often than not unclear whether a choice is benevolent, rational, stoic etc.
Overall I'd recommend playing on Expert anyway. Hiding numbers, aoes, dialog tags etc makes the experience much smoother imo.
PS. I guess I should have read your whole post before quoting because you're already aware of all of this. Apologies.