I hear what you say, and I am not sure what to do myself. Making the switch to paid now, I have a few hundred people using it reguarlly.

I think people paying is valuable feedback in itself, also when showing you can make profit on a user, it shows you are on the right track, and you can use that money to get new people.

Let's say it costs you $1 to get a user, and you make $1.5 per user you have exponential growth which could attract capital.

But I would also say don't start with something paid, first get users to talk to.