Well, yes and no. For instance (no pun intended), the site for your home instance is a page you’re going to be landing on a lot, so you’d want one which loads smoothly and reliably for you, and this often depends on your instance’s server infrastructure. Some larger instances are already being overloaded. Another concern is probably stability and longevity, since the fate of your account is tied to the instance that hosts it, so you’d have to choose one you trust. And the last one is moderation: you don’t want to join an instance where the admin is known for being shady and randomly banning people or blocking lots of instances. That being said, so long you choose a reliable instance it doesn’t matter too much which one it is.