I know when they got together for Crush/Sex Sells there were three batches of songs. The ones Jon wrote and stockpiled, the ones Richie wrote and stockpiled and the ones they wrote together (Garageland and Next 100 years were from the first batch they wrote together). I wonder if Too Much Of A Good Thing came from the Richie batch and they they tweaked it together, added/took out parts.

Looking at the lyrics and melody, nothing about it to me screams either Jon or Richie and I dont know enough about Richie Supa to know if it's closer to his style. It's the same way I'd bet a million dollars the second verse of Two Story Town was written by Mark Hudson.