Got it free recently too, and got round to giving it a bit of a try last night.
As above, I think it would have been better jsut setting the game in the past, rather than jumping between future and past.
They should have made the tutorial optional, the cut scenes should be skippable AND shorter. I am not far enough in to comment on repetitiveness, but the combat is quite shallow. I suppose after Ninja Gaiden, any sword based combat feels simple....
The game could have done with more role-playing elements - can see there is a lack of depth even with the little I have played.
Generally it runs well enough for how good it looks, but I do get frame rate dips into the 20's sometimes.
Will continue having a play through, but don't think it's the kind of game I will ever play more than once.