Actually I've always likened Purple Rain to A Hard Days Night. Both are associated with their first films, and both represent the artists at the peaks of their respective manias. Also they capture what may be the most enduring visual style and personalities of each.

But 1999 as Rubber Soul? Maybe. Albums packed with great songs. Individual styles well established. Well on the way to creative genius, but maybe not quite yet there. Easy to listen to, yet not pandering to pop conventions.