@benteh I have found that it's better to join instances that cover a wide swath. For the most part, I want to be on a furry or lgbt instance. But of course I can still follow people from art instances! Or politics instances if those get started.
The choice of instance only really matters for what your "Local Timeline" will show. The "Federated Timeline" will contain messages from your server and any directly-connected servers, and that will cover a lot more ground.
@huxley that was kinda my idea too.
join a big one, social, and find a great variety of people and build up a solid feed. then perhaps move to a smaller one, and bring that variety with me.