I think it’s a great idea. 
Features I think it should have:

It should go hand in hand with powerful keyword search across Nostr and within profiles / user history. 

Integrate users’ typical Nostr profile / history, but also include a “dating profile bio” that’s visible only in the app

Other things that should be a separate “layer(?)” in the app only:  
Age, sex, seeking, etc. 
Possibly some prompts users can choose to answer and their answers 

As someone who spent years on dating sites and is fully aware of their many problems, yet still found her husband on one, I have many suggestions if you want to pick my brains, devs.