The futuristic bit was a good device for keeping the story moving, that much can be said, but it sort of ruined the feel of it, when I bought the game, I expected gritty, pulse pounding assassinations, and sure, that's what I got, but what I didn't expect, or want for that matter, was a futuristic storyline tied into it.
It just didn't seem necessary to me, the whole Crusade-Era set Assassination gig worked for me, most of them time I forgot that there was a futuristic part to the storyline as well, other than the time when it kicked me out of the game for either killing too many of those fun loving mental patients who love to shove you with all their strength, or for doing all the assassinations in that part of the game.
The second part is understandable, after finishing all the assassinations in a specific part, it warrants an intermission because frankly, it's quite repetitive, I LOVED the actual assassinations, but it's just such a small part of the game...
It's by no means a bad game, it's not great in the sense that Portal was great, but it's not bad in the sense that Devil May Cry 2 was awful.
It let itself down a lot, the futuristic plot was not needed to drive the plot really, with an extra bit of work, the plot could've been driven entirely around Altair and the assassinations.
Really, overall from my point of view though; it was a fun game, it had it's redundant points and it dragged on a bit, but it was interesting enough and pulled me in with such finesse that I saw it through to the end, oh and...The assassinations were unbelievably fun for me.