[Geekette]

"We want (need) him involved but perhaps he does not share our vision? Or perhaps we need to be more flexible with our vision?"

Do you "need" him or his money? I can understand needing money but cannot understand needing someone who does not know your field/customers better than you, yet wants to force a significant product change. Which = someone who does not respect/have confidence in you. If you've got traction, find other investors; locally, get your AngelList game on, etc.

Likewise, being flexible with the path to your vision shouldn't be confused with changing your vision on a whim (someone else's for that matter).