I have just heard about this game recently, and I really like the teamwork aspect of it and I like FPS's, so it's right up my alley. ^_^ The only downsides are lack of local co-op and female characters (I'm a female gamer who loves playing as females and play with my sisters and younger cousins)
, but it looks really good and reminds me a bit of Borderlands and Battlefield with the classes and teamwork.
I usually play medics/healers/supporters in many games (if they allowed it anyway, like Dragon Age Origins, Battlefield, etc), so I would definitely be a healer in this game. (I love to roleplay healers so much that I spend most of the Infamous game healing random people, lol). I mean, "Medic" or, in the case of TV tropes, http://tvtropes.org/pmwiki/pmwiki.php/Main/CombatMedic, heh.
I'm one of those people who believe in cooperating and supporting than being macho and going solo, thus abandoning the team aspect. (Operatives are obviously an exception, though, lol.) Otherwise, what would be the point of a team? =)
The only thing I cannot decide is whether to be medium build or light build. I would have to see gameplay videos or actually try out the Light types to see if the sacrifice of medical supplies and HP is worth the speed.