I think complexity is good. I liked the massive amount of choice one had in D:OS2 and from what I see in BG 3 ALREADY (!!) there is even more of that here.
However, the class system is extremely complex, with the subclasses and "cantrips" vs. "spells" and all that.
So what this game needs I think is an introduction for new players BEFORE they create their character.
With D:OS2 (which I played for 1000+ hours according to Steam) I could do an Excel sheet for the first 8 (later, after I found out how, 9) character levels before respec, which included the civilian abilities as well, but with the complexity at hand in this game, I think many players will need an introduction to "what goes where".
Could be some kind of extra area where one can play around with classes, things like "wisdom" and "insight", etc...
Honestly, I don't feel like watching 80 YouTube videos about the ruleset before playing. Maybe it's a bit TOO hardcore for non-D&D-players to get into without SOME hand holding?