yeah the big one that i'm aware of Blahaj--although last i heard they were also spending a ridiculous amount of hosting money with no obvious revenue streams to make up for that so i'm not sure if they've got that sorted out
Sounds like you made more research than i did. I just saw blahaj so i joined this instance. Was waiting for an instance to have close to a similar feel than my lgbt reddit feed had
There are 15 LGBTQ+ specific instances on the joinmastodon list. More which aren't on the list, but any of these are a place to start. https://joinmastodon.org/servers
You can browse the local feeds of instances you're considering to see what others on that instance tend to post. More important IMO is that you find an instance whose moderation policy suits you. But you can always migrate to another server so don't over think picking one. Sign up, follow lots of hashtags and groups (in the Explore box, type in # or @ followed by various keywords for your interests to get started), follow lots of people.