I enjoyed the hell out of parts of it, but the RTS stuff drove me nuts.
Also, and this is just my wild speculation, but it felt very unfinished in the story department.
It was set up PERFECTLY for the 3 act structure: Act 1, the hero arrives, explores the world, wins a fight against the baddie.
Act 2, girl goes bad, world gets deeper and darker, hero loses.
But then instead of act 3, it just sort of ends.
The really annoying part is that it was all set up for 3 acts in terms of the enemies as well.
You got the hair metal guy for fight 1 with his glam rockers, the girl is fight 2 with her death metal emo kids and it was all set up to have Tim Curry be the final fight in some kind of hellish wasteland with his satanic metal cultists.
I know if you go back to the original area, it's kind of like that, but it wasn't nearly enough. I wanted the blasted face of Mars. I wanted a massive towering demon skull fortress built into the side of a volcano.
And yeah, the fact that more than half the game was shallow RTS battles was pretty annoying.
But still, the voice acting alone makes the game worth it. Add on that kickass soundtrack, great hack-n-slash gameplay and fun characters and I enjoyed it quite a bit.
Even more than that, I would agree it's one of the most important recent games simply because of how beautifully original it was. Like Bob said in the recent big picture, things like that need to be supported even if they're not all that great because otherwise we'll only get more sequels.