while reading about polyrhythm i found some interesting notation ideas. they use 'TUCS' notation or something, basically a grid where each box represents a unit of time. for rap you could use the boxes just to represent a semiquaver or a demisemiquaver (32nd note) each, and you could write the words and phrases inside them. the slower the phrase is spit, the fewer boxes it's written in

i agree with you that the words should be part of the notation. but i think it's also important to come to an understanding with normal notation too, even if it's cumbersome. like for instance i was thinking we need to invent a name for those little mini speed raps West Coast and Southern rappers frequently use. like when Dr Dre says 'i remember back-in-the-day...' on Let Me Ride. the other day i realized it's basically what in sheet music you'd call a 'trill'. and also there's maybe something to be learnt from the 'scansion' system developed in poetry (they call beats 'feet' and the 'time signature' if you will is like 'iambic pentameter', ie what type of feet and how many per line. and they've got a whole lot of names for poetic effects... i need to make a list of them sometime... you don't get this stuff on the internet)