I'm curious what are some best practices when you need to get initial feedback from real organic users, but your product currently has very few users (just beta launched for instance)
Be careful of bias. Users often aren't the best judge of their own experience - for example when Facebook launched Newsfeed in 2006, people said they hated it, but the data showed differently. Obviously, the feature actually worked. Particularly if your users are people who know you, they may be trying to make you feel good or to look good in your eyes, rather than giving an objective report about your product. If possible try and branch out and get feedback from people outside of your circle. Of course, feedback from folks you know is valuable too, you just need to be aware of the possibility of bias.
One user is all you need at first. Ask a friend or family member. When that one person loves it, ask a second. When they both love it, ask two more. Then four more. Then eight more. Then....