I can't speak for the YC experience, but in my opinion acquiring users for a product they won't stick with is like pouring water into a leaky bucket - you need

I can't speak for the YC experience, but in my opinion acquiring users for a product they won't stick with is like pouring water into a leaky bucket - you need to patch up the bucket first. I don't know the details of your situation, but based on what you've written, I'd first get your product to the point where your users love it and are going to keep using it. (Note that it doesn't have to be 'finished' at this point - just loved. It's possible for users to love a product you consider unfinished!) Then and only then would I ramp up user acquisition efforts.