In open world Int\Wis\Cha are pretty similar with exception that perception comes up WAY more often than others and in normal dnd games Cha is not that bad scince sometimes you have to split the party to gather info in short amount of time, here we have our game limitations, but my point was for player character. You will be talking with companions all the time, persuation will come up quite often regardless if you have other char as party face. Wis is diffirent because there are tons of spells that target Wis, dumping it hurts every character that is going to fight somthing with spells at some point. As i said, so far you dont have anything important that comes up with int, Cha at least helps you with companions.
Perception does come up a lot more, true. But the Arcana, History, Religion, and Nature checks all come up a lot more frequently in BG3 than I've experienced in DnD, which was my point. I'm sure there will be more as the game goes on. Arcana definitely seems the most important of the INT checks just because we're dealing with mind flayers.
Speaking of mind flayers though, their major role in the story definitely suggests we're going to be needing a lot more INT saves later in the game. I can't imagine people will use INT as a dump stat if they know 100% there is a big Illithid boss fight in Act 2 or 3.
