Eurosky actually looks like a promising alternative (speaking as non-european) but the AT protocol should have more open friendly competition than just the flagship instance of bluesky. Eurosky seems interesting as well.

Note that “instance” is Mastodon-brained and is a wrong way to think about atproto. The correct parallel is RSS / Google Reader.

Atproto has two types of things: hosting and apps.

- Hosting is like RSS. You can host your data on your own server and broadcast from it. It’s just an open source Docker container.

- Apps are like Google Reader. They aggregate from all hosts and usually build an index so they can show a rich view over the network. That’s what Bluesky, Leaflet, Tangled, etc, so.

So there is no “instance”. There’s hosting and there’s apps.

In addition to Eurosky there's also Blacksky, Northsky, and Anisota. Plus dozens of other non-microblogging apps. AT is growing pretty quickly now.