After playing for a bit I think that overall the combat will be less varied if 5e rules are enforced however right now we're in this weird place where some DOS combat is preserved while DnD rules are bent to accomodate. Mostly it has to do with barrels and surfaces. What is a big part of tactical combat in Divinity really has no place in Baldur's Gate. DnD combat doesn't rely around a rogue sneaking around and stacking 5 barrels of explosives around all enemies. It's a neat trick for sure, but I feel that it's gimmicky and doesn't feel like DnD.
Early game encounters in DnD are mostly swings and misses. They are not very exciting. But that doesn't mean that it should be replaced by a system of weird weapon skills and magic scrolls to spice it up. The progression to later levels reflects the character curve from simple combattants to proficient warriors to demigods all by itself. So keep the shoving, jumping (although not as a disengage bonus action) and other cool tricks but combat needs to be designed around DnD ruleset. That means a bit simpler early level combats but more "realism" which is inherent to DnD - loot is scarce but powerful, same for spells, enemies don't all have bombs and scroll to use etc.
I see the problem Larian has with early combat but right now it feels like reusing stuff from Divinity instead of embracing DnD to solve the problem instead of fully embracing the ruleset.
