I've seen several threads on people raising the front of the seat using 1/8" aluminum spacers; Reshaping the seats by pulling back the cover and adding higher density foam; and aftermarket seats.
I know that kawasaki makes a low gel seat. I know that corbin makes a very nice looking seat that has an option for a backrest on the passenger's portion. I like the corbin, but it is expensive at $435.
Look in the performance and cosmetic thread sections and you will find most of this info with pictures and more. Good luck.