I'm pretty comfortable on both ends of the GM screen; I like playing, but I also like running games. That said, though, I'm fairly new to Roll20 as a whole. I've used it a bit with some friends, but I'm still getting used to it.
I'm generally a fan of games that are either rules light, narrative-focused, or designed to emulate something pretty specific, like The One Ring (which does an amazing job of using mechanics to evoke the tone and feel of Tolkien's writing).
I'm willing to put up with really crunchy games if they're attached to a setting I'm invested in- Shadowrun in particular. I really dig 2e and 5e Shadowrun, both mechanically and in terms of the tone of writing. I'm way more "pink mohawk" than I am "black trenchcoat."
They're not listed on Roll20, but I'm a huge fan of the recently translated JRPG's that have been published in the last few years. Tenra Bansho Zero, Double Cross and Ryuutama are games I'm really interested in playing or running, especially Ryuutama.
I'm a little picky when it comes to World of Darkness games. I really prefer the New to the Classic, though I have a very soft spot in my heart for 2e Vampire; the Masquerade. Vampire, Werewolf and Geist are the NWoD games I'm most into.