Inquisitor is basically like Lionheart without the good writing (though the world is interesting), with extremely predictable plot twists that are reused several times throughout the story, even worse combat, terrible game balance, game-breaking bugs (quests etc. that are unfinishable), an even more awkward user interface, horrendously bloated, overlong and extremely boring dungeons against endless copy-pasted trash mobs, bad pacing, minimal variety in gameplay except for the odd puzzle, a crappy loot system with almost zero progression throughout the game that lets you get the most powerful gear by re-visiting shops a few times...
... but at least it looks gorgeous and has nice music.
If you want to compare it to Neverwinter Nights, Neverwinter Nights is pretty awful but at least it has mods and multiplayer. Inquisitor does not.
Archimbaud: If you really liked Arcanum, you will like Inquisitor.
Why ? Because for both games, there some high flaws in gameplay and balance. Yet, the story is so attracting that you don't really bother.
On the contrary, if Arcanum was painful for you, you should play another game.
Bullshit. Arcanum has better combat, better game balance, a far better character system, more mechanics (crafting etc.), a far bigger and more interesting world, excellent writing and a solid story, good quest design with some nice choice & consequence from time to time, a game world that is much more vibrant and alive... it's kind of broken in a few ways but the core gameplay is so good that it's easy to overlook. Inquisitor just sucks, with any good qualities drowning in an ocean of patently horrible and boring combat.
Arcanum is possibly my favorite 2D RPG of all time and Inquisitor can't even hope to lick its boots.
Sabin_Stargem: However, the saving grace of Inquisitor is being able to investigate people and their stories, which could be interesting as you piece the truth together. The problem is that the combat is not just a foil to the roleplaying, it actually spoils things because it serves as an obnoxious barrier to the good stuff. Unfortunately, there is a lot of combat in the first act, so your patience and desire to see the roleplaying through would be seriously tested by the bordom.
Act 1 has the least combat of all the acts. The others are filled with between 2-4 times as many dungeons and in general, while the environments are also bigger, there aren't many more quests or characters. The game gets significantly worse as it goes on, but the non-combat stuff does get a little better. Shame that all it amounts to is clicking on dialogue options until they all disappear and witnessing the 100% linear story with almost zero choice & consequence.