I think a lot of us would have appreciated a more optional approach to a lot of the story stuff back at the base. Some of it can go on for a long time, may not be particularly engaging or exciting, and can just leave you wishing you could get back to the combat loop. Also, what's up with that walking/jogging animation at the home base? I've spent $50 in the Unreal store and imported motion captured animations, ready for use in a commercial game, that looked better than that and could be hooked up in a few hours.
It's a very good game that, when I recommend it, typically comes with an asterisk attached.