Well, I’d stick with someone who’s had his level 52 review (so chuck DP). The remaining question is then:
Do I want to pursue a hybrid build, or am I okay with pure melee?
I prefer the melee only playstyle myself, but I will definitely say that being able to have at least a couple of attacks which can do damage at range is nice given the ridiculous amount of ground spam crap in the game. NC is pretty much pure melee, as is DD (to the best of my knowledge; though I haven’t played him since his rework. I got him to 60 before that; need to prestige and give him another whirl but they’re releasing people faster than I can level them!). BP has a ranged build (though I have no idea how worthwhile it is), and Spidey apparently has a pretty decent ranged build.
I feel like, in general, NC and BP are similar (close ranged melee with some nice AoE stuff), though NC’s travel power wins by a mile of course. NC is probably one of the better green/red terminal farmers (if you want cube shards) simply because it’s so easy to get him to the boss in 30 seconds or less. The only place where this is somewhat challenging is AIM because of the maze-like character and having no idea which way you should go. Hydra base is also a bit like this, but the layout there seems to be less likely to mislead me.
However, when it comes to cosmics, while NC does just fine on trash, I feel like he has some issues on bosses, particularly with the recent nerf to X-Slash. It used to do enough damage to make up for having to stand there and get potentially pummeled by the boss, but now it doesn’t do the extraordinary damage any longer, and with my current build, at least, there really isn’t a way to layer on a whole lot more damage.
My Spidey does pretty good at wrecking cosmics, though he tends to vacillate in health while doing so. He’s very mobile (as is NC), but seems a bit tougher than NC (despite being roughly undergeared). I’d worry a lot about DD in cosmics because I don’t think he normally is sporting an avoidance-based movement power (I found, for example, with Emma in cosmics that movement powers that jump over power cosmic or teleport are far, FAR superior to dashes and rolls, because the latter leave you taking damage if you go “through” the ground crap, while the former don’t.)
BP is interesting, because you can generally choose to disengage when you want due to his stealth. You can do this with NC too, but if you have points in BP’s bodyguards you can keep things from resetting (which I always find annoying) when you stealth, and in general it’s far more viable to pop out of stealth, lay down some damage, and then pop back in.
Frankly, I’d get them all up to level 30 at least and then decide who you want to main after that. Better yet, get them all up to 60 and decide. In my world I tend to lose interest after I get a character to 60 and decently geared, and then move on to a new char. That’s what I love about this game, there’s always somebody new to play, and more times than not I find something to enjoy in that play style.