I started on kbin.social to get my feet wet and once I figured things out a bit I wanted off the flagship instance so I could help with decentralization. Purposely sought out a smaller instance, but I, like the user you replied to, needed faith it would keep running. Server age is useful. How many people joined is also somewhat useful—you’ll probably have a harder time deciding to shut down an instance down on 100 active users than on 2, although it still happens (I used to be on kbin.cafe with around that number, the admin went inactive and the instance lived for awhile, but I checked now and get an SSL error. Shortly after the admin went inactive I went looking for somewhere new. kbin.run had around 100 active just like kbin.cafe, I went there, and clearly it worked out). I did not really need any fancy features, just for the instance to have a future while not being one of the biggest ones, and to not have a horrible reputation (like explodingheads does).

You might get a new signup from me, already happy with my current instance, if your instance is devoted to an interest I like. If someone makes animals.social or bunnies.social and it gets more than 2 people to sign up, I’m definitely unsubbing from all my cute animal communities here and resubbing to them there. But I get the feeling you want to be general purpose. I don’t think I’ll need to make a new account anytime soon but if I do I’ll come checking on yours.