Because of this, I had the idea for how to solve it. I recently I finally started spending a few hours, here and there, putting together an MVP. So glad to say that it's ready for testing and to earn some feedback!
With this finally out there, I hope to learn if there's a market for Inviteable. It's very similar to Facebook Events, which I know gets plenty of use, so at the very least, I would think the market exists for certain groups.
I hope that Inviteable can help fill in the gap, and is a platform that provides a simple UX that accomplishes the basics exceptionally well.