Backstory: Have you ever tried to develop a new brand? We're going through that right now and it's a pain. We're starting to return to previously rejected ideas and we've forgotten why they were originally rejected.
The Idea: A website to help create a brand name.
Deep Dive: Similar to a mood board, you would build a web platform for customers to create a brand name board consisting of words and pictures. You would give them the ability form a web, linking similar ideas. The purpose is to derive meaning and vision in the name by narrowing down concepts until you find a name that fits.
You could also build a comment system to keep track of rejected ideas.
Validation: We're using white boards for this right now.
Monetization: This is hard to make a SaaS product since it's not a service you use frequently unless you're a branding agency. You may want to have two different pricing models, a one time for small companies and a monthly sub for agencies.