My advice is, make whatever build nobody else seems to be making then make the HELL out of it! Flesh out the bio, come up with a good theme and a costume.
Since you've likely got "The Funds", throw in as many Purple sets as it will hold, ATO's, Winter sets, build in MIDS then throw money at any perceived problems, and find a way to play it which makes others say, "Damn. I never thought that combo could ever even DO that."
Remember that this is a 20 year old sunset game being upkept by a supremely awesome crew. There are likely more missions in game than I personally will ever actually take the time to finish, so these days I find my own fun. Make a character that stands out, one that makes others laugh, regardless I try to make them my own. Whatever you do remember, games are supposed to be fun. Unless they're your job, then I guess they're work.
Anyhow, if you find that you're not having fun doing anything at all in your free time, I advise you find something else which is fun to you, and then do the HELL out of it.