Can it be improved or is this the best when compared to other installs you've seen?

Yeah you look as though you've got it to the level it should be. I guess you're using 3DFX mode and a version of the dgVoodoo glide wrapper?

No, it can't really be improved upon. If you haven't already, you can force a higher screen resolution via dgVoodoo and force triple buffering, plus make sure everything in there is set to 32-bit. That's all there is though!