For my first entry I went simple and classic. I used "tetris" blocks to create the initials and used nice, bright, fun colors. The colors can always be changed if you don't like them.
Also, the blue frame represents an enclosed area (play "space"). That's just a little bonus concept
experimenting with a "line" achieved (think tetris). I'm sticking with the tetris theme because it is one of the most addictive, fun, universally appealing and memorable games of all time and you can find a version of this game on almost any platform.
Another thing to note is that these colours work very well on both light and dark backgrounds. Even I was pleasantly surprised that I didn't need to alter any of the colours (except "playspace" of course) :)
I want this logo to be simple yet original and memorable. Hopefully that's what you want as well. I've tried to use designs that have the same unique look even in one colour