It's also possible that maybe the OP would benefit from separating and moving on to pursue the live he wants to live.
I say this because I'm in a similar situation myself. I like my gf very much. She's one of my best friends. However we've grown apart since we met 2 years ago and I can relate to all the sentiments of the OP. We just don't have enough in common for a long long relationship of decades, and we'd both be happier apart, though I'm not sure she recognizes that yet. My intent is to move on, but I'm sticking around until she gets through a big stressful life change that should be resolved in 1-2 months.
At the end of the day, I would imagine the the OP is not struggling with her not being as intellectual as her, but that she simply doesn't share the same values. He sounds driven, curious and autodidactic and she sounds like she is seeking comfort, acceptance of the status quo and wanting to settle down. If they don't share the same values or at least are not at the same place in their lives, should they even be considering raising a kid together? Although I feel the same as the OP, I realized that all those sentiments ultimately derived from fundamental differences in personal values that as far as I can see are irreconcilable. I don't yet know when I want to raise a child, but I do know how I want to raise a child and what kinds of values I want to teach them and those are not aligned with the values of my gf.
Remember, it's also entirely possible that there is more to life than trying to salvage the project that is "your wife, your marriage, and your relationship". I helped keep my parents marriage together for 16 years and I regret the last 7 years of doing that. They would both have been much happier than they are today had they separated in 1999 instead of 2006.
The question is about what kind of girl you'd like to have instead of your wife. Or at least, that's how it comes across...
It appears that you see her as liability rather than asset. First, change your outlook toward your wife. If you can't value her properly, you are not going to value anyone else either. Startups require lot of sacrifices not only from you but also from others involved. Spouse and family do the most sacrifices to achieve entrepreneurial dream of a family member. Putting them down is not going to get you far. Learn to respect what others bring to the table.
I will suggest you forget about being "entrepreneurial" and focus on salvaging one project "Your wife, your marriage, and your relationship". Once you recognize the positive qualities of your spouse then talk about growing the family or becoming entrepreneurial.
ed: Apologies for being rough in my response. The OP just touched a raw nerve.