Those who played it never said it felt floaty, but instead the opposite. You also have pretty much 0 air control without using jets. At the moment it really doesn't sound anything like Legions other than having jetpacks and skiing, and if you've been following the game you should know this by now. 0 chance of it having Overdrive, downjet doesn't sound likely either. Chasing seemed to be an issue many brought up during the PAX build, which the devs are addressing. Seem to be putting more effort into art than physics, which is (very) worrisome with a game like this but I could likely be wrong.
To be honest I'm not really sure why a Legions player would be all that interested in MA. The devs are leaning towards a T1/T2C remake, while Legions is a very stripped down version of those games. The simplicity and movement of Legions is what most people enjoy(ed), neither of which will really be present in the same form in MA. Different movement, more complex gameplay with assets and armors, very little air control, no regen. Don't expect Legions 2, even if it started out as that.
Also see FishStix's thoughts:
https://www.reddit.com/r/Games/comm..._like_game_coming_soon_pax_prime_2015/cv8823q