Re: Crafting a good profile and opening response.
Bleak is right but you're on the right track for recognizing that. XD
As far as interests go, music is pretty generic. Gaming isn't going to win you any brownie points. Dancing is good. Remember you want to list the things that set you apart from your AFC.
Nice; responsible; good sense of humour: These are all also pretty generic. Especially stay away from nice. The working out/in shape you can show with pics. Exploring the city (do you mean flâner or urban exploration?) and, again, dancing are good angles. Maybe list some of your favourite places to go, and what makes them appealing. Never underestimate the power of good syntax.
Your line, "[I]'m pretty much looking to build a legit relationship" is pretty good. I'd leave out the bit about needing one as filler for when your buddies aren't around.
As for your opener, personally, if someone called me cutie in the first line I probably wouldn't respond. I'm not too familiar with dating site etiquette, but I'd probably go with something to the effect of,
"Hey, I was looking at your profile and you seem pretty cool. I see you like [common interest from something in their profile]. [Opinion about common interest].
I'd like to get to know you better. Maybe we could chat sometime? Let me know what you think."
you are a soul playing a game of human
might as well unlock all the secret areas