Alpine rock in the sierras is pretty good as you seem to know. But….if you are in Squamish and going to the Wind River Range…. then make sure you got to the Bugaboos. It is more or less on the drive…..
The Bugaboos have got to be the best "non hard core" alpine granite ever. The routes are not as busy as the carpark suggests. If you want alpine choss then the rockies are not too be missed and are also on the way. The Selkirks and mysterious northern BC granite also looks uber good - but info a little scarce. I haven't been to Wind River. It looks good, but for what it's worth, it does not look as good as some of the stuff in Canada.
Elephants Perch (Idaho) also worth a visit if you are driving past for long back country granite routes.