What bothers me isn't that Kes left.
It's that Kes left when she was obviously possessed of a lot more dramatic potential. The damn time episode showed a ****load of interesting stories that could have been done with her.
They just...didn't.
I feel the same about Robert Beltrane and Chakotay. Everyone complains about Harry Kim not getting enough development but after his "Seska-baby" plot, did he REALLY have anything to do?