Are data structures like entityState_t used by other VM's? I wanted to delete everything inside cgame and slowly start to replace code, rewriting everything with better code (i intend to use C++ and OOD).
If you want to use C++ you will need to drop vm's and just natively compile the whole game. Or you could add a q3vm-target to a C++ compiler (that would be really cool). The modules game, cgame and q3_ui uses C and the lcc-compiler as sort of scripting language.