Mojotron is an action game for Linux/X Windows inspired by Robotron and Llamatron
I really dislike when game describes themselves only in those "like foo and bar", where neither foo nor bar were even considered to be given "foo-like" or "bar-like" candidate. Unlike doom, quake... (which are well-known enough to have games named doom-like or quake-like).
I think this makes the game less likely to be discovered by new players, because it feels so cheap...
In conclusion, I think you should start by updating that description before even doing more artworks replacements or the like.
I understand you're not the author, but, since you're hosting a copy...