Isaac Hayes losing control of his music/licensing has to be one of the most depressing stories of the time, jeez.
But yea, Motown was built almost solely to product hit crossover records - pop enough to appeal to mainstream whites, but funky and soulful enough for blacks. It worked perfectly, but I also prefer a lot of the Stax stuff for its ambition and emotion. Also, I often got the impression that a lot of early Motown was far more single oriented than album oriented - when you think of great r&b albums, not many Temptations albums come to mind per se, whereas Hayes has multiple amazing albums, Otis Redding's first album is great, etc.
In hip hop terms, I guess you could compare the two labels to Bad Boy (or Roc-a-Fella) and Loud. Bad Boy of course being the Motown of hip hop hits for awhile, with some of the cleanest (and best mastered) stuff, alongside very poppy/r&b hooks. Whereas Loud was the grittier NY shit, from Wu Tang to Mobb Deep.