I have to agree with you on most points, though I actually enjoyed the sliding into cover. I'm actually not a big FPS fan, just like that I can use objects in the world to hide behind and actually stick to then peek around to take my shot with my bow. Aside from that, yes your points (I have no real desire to try multi-player) are all valid. I would have like to see better finisher animations. They were cool and all but very choppy and caused a ton of clipping and other odd graphical issues with the enemies on the PS3 version. More weapons and an inventory of some sort would've been nice too. I feel the story was going along well and then all of a sudden it was like we were rushing through to the end. I remember actually thinking to myself towards the end, "I haven't encountered any puzzles in a while."
To summarize, they had a lot of potential with this game but unfortunately, it feels like they rushed through it, maybe due to deadlines imposed on them or budget constraints? I would love for the same group of people to tackle another game just like this because now they have some experience and can take that and some fan feedback into the next one...not a sequel, but a different story and setting altogether. Come up with some of their own lore or even base it on something in medieval history. And don't rush it the next time around. Flesh everything out because I would think most RPG players are not looking for instant gratification. Anyway, great potential with a fantasy RPG done in this style. If done right I really think it could be something awesome. They could add a multi-player "arena" if they wanted but keep it separate from the single player campaign or come up with a better way to make it work by playing the campaign with a friend, the way Gears of War did.
Anyway, that's my two pence and overall, I have to say I did actually enjoy the game and had fun playing it. No replay value in it though.
Cheers!