In the prologue and chapter 1, Witcher 2 combat is about as good as Arcania. Enemies swing weapons around like idiots -> Geralt dodges and hits them in a back.
In the chapters after that, it's about as good as Dragon Age 2. It just boils down to activating Quen, spamming the left/right mousebutton until the adrenaline bar is full, and pushing the Awesome X button. Against bosses that use your own cheesy tactics against you, either spam bombs or use daggers.
There's not much to like, really. It was more entertaining in the first game, where new animations would unlock the more you leveled up your styles. The first game also managed to capture the superhuman speed and reflexes that witchers are supposed to have, whereas in the secodn game Geralt moves around as a geriatric.