Go with a trial instead of a free plan. If your users find value in your service, they'll buy. Put a feedback form on the page that notifies them their trial

Go with a trial instead of a free plan. If your users find value in your service, they'll buy. Put a feedback form on the page that notifies them their trial has ended. If they don't pay, they might complain and give you feedback. Also, you can collect emails with a free/trial plan, so use that to get feedback and/or try to sell to them again after you pivot on the initial feedback.