I don't know Bluesky, but of all the microblogging software, I think Misskey and its forks like Firefish have the most functions. For example, content can be structured well via Antennas/News-Picker: https://thefedi.wiki/firefish/user/antennas. And you can also add accounts you don't follow to lists (which is not possible with Mastodon, for example).
Firefish, with the antenna feature
I'd say in general this would be Bonfire but it's still in active development and not yet ready to run stable as a public instance.
I mean, I consider Mastodon pretty "customizable" in the sense that you state. It's easy to follow individual hashtags surrounding specific topics, groups that people use to post about a specific topic or individual users. My home timeline is pretty much all topics I'm interested in due to who and what I follow.
Similar to Lemmy really. Your subscribed feed should be exclusively topics that interest you from the communities you subscribe to.
Friendica has a group, real groupe! And they can be available (Misskey groups only for Misskey not for outside!) Compatible with Diaspora can communicate and other things that can propose Misskey.
Overall, Hubzilla certainly has the most features, but Friendica (which is also my preferred software in the Fediverse) also has a lot of features and the largest reach. But it is probably not similar to Bluesky (which I don't know). Friendica's federation with Lemmy is very good and (Lemmy-) threads are displayed more clearly than in Mastodon, for example.
A community dedicated to fediverse news and discussion.
Fediverse is a portmanteau of "federation" and "universe".
Getting started on Fediverse;