It's different from 2 in the sense that you won't have mobs of enemies appearing out of nowhere around you, not very often at least. If you want more you'll have to be more specific on what you don't like about 2.
Well basically every single part of it is bad, so I dont even know where specifically to begin...
Heres an attempt anyway.
Are the enemies still randomly immune to specific damage types for no reason?
Are there still enemies with infinite access to healing potions who take thousands of casts of your most powerful combat skills?
Are there still enemies who hit your guys with instant kills from accross the map?
Are there still enemies which freeze your guys in place in order to make it so you cant avoid instant kills? Not using skills, but simply causing your movement to stop for no reason.
Are tanks actually a thing which exists in :I?
Do your crowd control skills actually work in :I? (Ie taunt, stuns and such)
Are the spell and skill comboes actually impactful like they are in : O or just "oh hey you do extra damage now because blrghtgrt"?
Does how you build your characters actually have any effect on thier performance?
Does every fight devolve into one of your characters running from the horde of enemies like a goddamn benny hill sketch peppering them with damage skills whenever possible and just hoping against hope that they dont get frozen by one of the instakill attacks?
Do your characters and the enemies bark stupid **** constantly?
Does any minor change in elevation break the combat?
Do your melee guys do AOE damage for no reason at all meaning you cant have more than 1 melee guy like in :2?
Do your followers ever get above 60% to hit, like in : O, or are they never capable of applying damage like in :2?
Do your followers actually obey things such as "dont move" or thier tactic settings?
Can you actually equip your followers or are they essentially naked like they are in :2?
Can you make your followers perform roles in combat, like in : O, or are you stuck with them potentially always being useless (like Merril/Tattooed ****** melee guy)?
Does every combat start with your PC saying stupid bollocks and then a thousand enemies stream out of every crevice in the map?
In a lore where teleportation is not a thing does every single mage you fight teleport everywhere like in :2?
Is your gear as fugly as it is in 2? (Not really combat related, but kind of is...)
Probably more, but just thinking about DA:2 makes me want to drink myself unconscious.