We are looking for something that is playful and fun at first glance. The idea is to cater to a group of predominantly male visitors in the range of Late 20's to Mid 40's. Definitely something very contemporary, but not bland or overly simple. Hence we are open to the idea of building a character to accompany the word mark (something a little more vector based - see references like TokiDoki and BadJuju brand clothing). However this is NOT an absolute requirement (just a direction we need explored.
Pinball games are full of vibrant colors and somewhat showy. Even though this is a free classifieds marketplace, we don't want to sacrifice and end up with a horrible "craigslist" style brand. We plan to build a presence that is fun. An example that we found from Bad Juju Games on Facebook. Look at their Banner for reference: https://www.facebook.com/BadJujuGames
The idea of using a vector pinball in this style is 100% on target in our opinion. The other is the 80's style font used in "Balls of Steel". These are really great ideas that fall in line with the direction that we would want to run.
The logo can easily support gradients and should be powerful in terms of color. Keep in mind, however, something predominantly one color might make for too much in terms of the website. Pink of course is more feminine, so in terms of color it's at the lower side of our list -- But the logo example below really benefits from the pink lettering. I would say, "take some risks". Go loud, but don't alienate (if that makes any sense). Go playful, but don't end up in "mickey mouse" territory per se. Adopt a little bit of 80's/90's style and characteristics.
Also, anyone that wants to look up references, here's a few top games for inspiration: