if you're an rs1 fan, the rs2 is an interesting, and not necessarily inferior, variant grado flavor. it'll give a great, gutsy, rendition of the blues! the alessandro ms-pro is a more neutral variant of an rs-1, and is an excellent choice too. if what grabs you about the rs1 is it's sheer toe tapping quality with popular music the hf1 mod done by headphile, the hhf-1, is not only a beautiful phone, but a highly pleasurable one too.
The RS2 is not as clear and defined as an RS1 but lots of fun to listen to, it is a great value for money headphone in the Grado line-up IMO.
For a different feel headphone I'd suggest one of the discontinued Denons - the D7000 will be sort of similar to RS1 while D5000 will sound more like the HF2.
The comfort with the Denons will be 10x better than the Grados, however the closed can nature might take a bit of getting used to.
I used to be a Grado aficionado myself and was won over by the Denons if that is anything to go by.