I definitely think there should be Variant Humans, or at the very least, the standard humans should get tweaked. Some things have been tweaked from the pen and paper rules, such as changes to Ranger, so tweaking Humans wouldn't be out of line either. Wyll and Gale should also become Variant Humans if they get added.
There are many ways to tweak humans, and many would be fine without giving them a feat.
- Humans get a +2 / +1 ASI which float (they can go anywhere) instead of +1 All. That would obviously look weak if BG3 adds in floating ability scores from Tasha's to everyone, but I don't think they'll do that.
- Humans get two floating +1 ASIs, AND expertise (double proficiency bonus) in a skill proficiency of their choice. That would work with the "Jack of all trades" type without granting them special things like Darkvision.
If certain Feats are too strong, they could add Variant Human and level-gate those Feats so that while they can get selected at level 1, they don't come fully online until level 4. Or alternatively, at level 4 the Variant human gets both an ASI and a Feat. (Possibly they can exchange the ASI for a second Feat, but they won't be able to exchange the Feat for a second ASI.)
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If Larian, as presumed, won't be allowing floating ability scores in the game, I do want rolling for stats to be in the game, to allow for more variety in character builds. For instance, if I want to make a Wizard from a race which doesn't normally get any bonus to Intelligence, rolling would let me get a 16-18 I could use to allocate into INT.