The main mechanical hurdle of the latter suggestion is making sure all enemies are Surprised for their first turn. But BG3 already does something like this, no? I've seen many reports that attacking from stealth leads to the PCs getting an entire turn or two before the enemies can go.
Yes, it's a bit hard to work out what's going on when the mechanics are so off, but I think what's happening when you successfully attack from stealth or distance and then an enemy spots you and your party (which is more likely if they're not in stealth!) then things work much more as we've been saying they should. At that point, everyone - the party and all nearby enemies - roll for initiative and combat starts. But because your party attacked out of nowhere the enemies are surprised and can't do anything on their first turn. The main difference between that situation and the one we've been discussing is that the initially attacking character doesn't automatically go first, they just get their turn wherever in the queue they end up, but they get another full set of actions and bonus actions, with their first attack that started the fight apparently considered pre-combat.
I just wish it would work in a similar way when enemies didn't spot some or all of my party!
