I agree with you about the fact there are too many rap songs with too much profanity etc etc, but i dont really know of anything that's "profound",but there is stuff that's "intresting" (that's the only way i can put it) to listen to...
Listen to "alphabet aerobics" by blackalicious, that's what started it all for me (i used to hate rap before that), and it's the most easy song to "get" that's pretty much based on the RAP.
The other thing that work really well is the drumming... but to be fair echo on drums is very cool, except 80's cheesers went and over used it. (Martin Hannet's work on Joy Divisions first album back in 77 or 78 was the first time that some one very delibaratly put echo on drums and got a great sound, just listen to "atmosphere" by Joy Division.)
I do definetly feel that rap at the minute is at a low point. but that's not say there's nothing good about. It's always worth a little probing, and reaserching, cos there's some great rap out there, just like punk, amidst all the crap... but i do definetly get the impression that poeple fail to ever hear great bands/ artists because of the crap that surrounds a genre.. which is a shame, cos it ends up poeple like mediocre middle of the road stuff like "nickle back" simply cos they've not heard anything better...