The first 10 minutes are frustrating as hell, because you haven't gotten augmented yet. After my first playthrough, I honestly thought that was a conscious design decision. Since everything in the game is related to the practical and ethical challenges with trans-human augmentation, they made you really fragile in the beginning to contrast your power level as a regular human with your power level as an augmented human.
This could just be me over-interpreting things, but it does make sense to me at least :V
But no, it's not that hard. It is a relatively challenging game unless you're playing on the lowest difficulty, but if you take it slowly, the missions aren't that hard to get through. The bosses can go fuck themselves though.