The colors in the first three pictures is just too much for me, they make my eyes hurt. I do like the final picture with the green mods and orange alphas, but mostly because it looks like a ninja turtle. However my reaction regarding all the mockups is that the green legends on the orange keys are just not very pleasant for my eyes to look at. I honestly think plain old white would look nicer. Any interest in turning it into a ninja turtle set?
You could have some cool symbols with the weapons, bandanna/mask, pizza pie/slices, a rat and 4 turtles, etc. Not copywritten stuff, but rather more symbolistic/generic.