Any suggestions for how to optimize the var's from vecterror and CadillacV8? ...
I highly advice you to
not do this, but here's how you could reduce the amount of "clutter" which those *.var files might add to your installation: unpack those *.var files (manually, or by using the integrated Package Manager) and delete all the stuff you don't want and which isn't needed for the "look" (if you just want to keep the look itself).
The issue with this is: you'll need to know exactly what's needed and what's not. And you will end up with a lot of loose files, which is not what you want. Also, if another resource has this *.var file as dependency, you'll need to re-download it again anyways (VaM doesn't know if you have the *.var file installed if it's unpacked).
So in general: you don't want to mess with *.var files. If your VaM gets "too slow" because you have "hundreds of these" bloated *.var files installed, maybe it's a better idea to get rid of some of them, because I doubt you will use all of them. 80% of them you probably don't ever use ;-)