Yeah I'll agree it's a bit repetitive in nature, even frustrating when you're trying to run away from hordes just to save yourself the time. The Nemesis system is great in creating grudges, and kept me coming back for more, to finally put down that son of a ***** who got the lucky shot on me and mocked me for it. But I thought it was a great game. Sure, the environments could use a little more variety, but I gotta say this: at the time I played it (around halfway through last year), I was really, really sick of open world shit, and was just not in the mood. I only played it because of my friends and the internet recommending it so strongly, but I don't regret it one bit. Even played through the DLC, and did quite a bit of the side stuff, getting damn well near 100% completion, which I never do.
So yeah, I'm hype for a sequel.