[Benny]

There will be class and race specific abilities that you gain access as you level up. Enforcers will have heavy armor and can take much more damage, naturally making them the ones you have fighting in the front. Avengers got medium armor. Phantoms got light armor, and dosen't take much damage. They need to be sneaky and have a good aim (I think the phantoms have cloaking / invisibility as a class ability. Heard someone say that in an E3 video)
We'll probably not have damage reducing stats, but there's an ability that causes headshots dealt to you not to be instant-death. Maybe other abilities that enhanches your survivability? We don't know that yet.
As for stats on your performance, I think we'll have stats such as aiming and speed...and similar things. Strength and intellect dosen't have much to say here though.