on the note of dynamic opcodes, which I think LE grabbed from my work on emu, you might also consider grabbing my perl packet tools (maybe convert them to python if that makes daeken happy).
http://www.eqemulator.net/wiki/wikka...ka=PerlPackets
basically lets you make packets on the fly, without recompiling (just reload your perl file). Or even read them in hex from a file and not even have to reload your perl.