Generally, I think combat has improved - enemies seem to be making fewer dumb decisions (although too many of them are attacking the invulnerable flaming rock, and there's still way too much casting of sleep on characters resistant to sleep and characters with too many HP).
The Gith fight is harder, and while some of the loot is better, there's no Gith half-plate any more, which makes it less worthwhile. An enjoyable challenge though.
The Mephits are way too easy! All the neat game design that went into the original battle location is now wasted. I like that the Wood Woads now start in a regenerating position, but have they lost their tree-teleport ability? Sneaking up on them by jumping across to the island further west is now pointless, and the extra (easily solved) difficulty of the jump across the water to get to them from the front has been removed. (Am I also right in thinking that a lot of other jumps that previously required crates or strength boosts are now easier?)
The Hag is also too much of a pushover, literally. You can kill her in her hut without much problem, the traps on the rocks no longer reignite, and in the final fight itself you can now just position your party/sneak behind her and take away most of her hit points before she does anything. You can also just sneak up and shove her into the abyss, which is easy sleazy cheese.
(A brief aside - not sure if Auntie's well is now working as intended - it gives you an HP boost but then a handicap the following day, regardless of whether Auntie is alive or dead, whereas before it gave you the boost with no handicap if she was dead.)
Overall, the combat was more fun, I think, but IMO Larian have made a few too many concessions to those who were complaining about certain fights being too hard.