OK I lied. I originally said that the only problem I had with Divine Divinity was the randomness of the treasure generation system (which is thankfully being overhauled in Riftrunner). But now I've thought of something else I disliked - the English voice acting. I know that a lot of other games feature equally atrocious voice acting, but Interplay and Bioware games have raised the bar, and I'm not satisfied with anything less than that sort of quality.
Now since Riftrunner features fully spoken dialogue, I can only hope that Larian invests a bit more on the voiceovers. Not that it'll stop me from buying the game if the voice acting is bad - I'll just turn voices off so it will be a wasted feature.
I also hope that having full voiceovers doesn't result in less in-depth dialogue. That's one of the mistakes Origin made with Ultima IX, and look how well that game was received (sarcasm alert!). Obviously this is a matter of personal preference, but I like reading (or listening) to loads of dialogue.