Sorry, I don't know about syntax files.
The vim :highlight
command shows names and associated colours.
The terminal can handle as many colours as are shown by tput colors
/usr/share/vim/vim72/colors/* files are useful examples.
To experiment with vim colours, copy a /usr/share/vim/vim72/colors/* file to ~/.vim/colors and modify it.
In ~/.vimrc, try set background=dark and see if vim adjusts itself (didn't work for me).
Here are some .vimrc color adjustments but mostly for light background so only useful as examples
"hi LineNr ctermfg=grey guifg=grey
"hi Statement ctermfg=black guifg=black
hi Identifier ctermfg=darkGreen guifg=darkGreen
hi Comment term=bold ctermfg=4 guifg=#406090
hi Constant term=underline ctermfg=Red guifg=#c00058
hi Special term=bold ctermfg=Blue guifg=SlateBlue
hi Identifier term=underline ctermfg=Black guifg=Black
hi Statement term=bold ctermfg=Brown gui=bold guifg=Brown
hi PreProc term=underline ctermfg=Magenta guifg=Magenta3
hi Type term=underline ctermfg=Green gui=bold guifg=SeaGreen
hi Ignore cterm=bold ctermfg=7 guifg=bg
hi Error term=reverse cterm=bold ctermfg=7 ctermbg=1 gui=bold guifg=White guibg=Red
hi Todo term=standout ctermfg=0 ctermbg=3 guifg=Blue guibg=Yellow