Type r_picmip 6 in console

/r_picmip <number from 0 to 16>

followed by /vid_restart

I think a fair amount of gfx options are now covered in the menu so have a look there.

r_vertexlight 1 to remove world shadows

r_dynamiclight 0 to remove point lights like rockets and quad aura such

try finding some pr0's old cfg, put them in your baseq3 directory and /exec <cfgname> to try them out

Thanks for help