I like the idea, but not really digging the novelties. What is the ghost a reference to?
The Pac-Man ghosts, if I'm not miskaten.
I quite like the set, myself, but I can see other's points about the colours now that they mention it (but I liked them originally and still do for the most part).
In terms of mods, I'd love to see more inspired by DOS or Unix to fit the old cyperpunk aesthetic from the 80's and 90's. Maybe like a command prompt style one, or even some urban/punk styled things (maybe like spraypaint aesthetic and so on). I do agree with others that it would be nice to have some original art for the deskmat, as it may cause you a copyright issue down the road, so best to play it safe!
It's great to see that you're interested in getting feedback, and I really like the direction of the set so far. Hope to see it happen in whatever final form it takes! Good luck!