Try https://lemmyverse.net/communities

It has the sort/filter options I think you’re looking for, and it doesn’t limit info to your instance’s perspective. (It always shows all instances, even if your home instance hasn’t made a connection to one yet, and it shows total subscribers across all instances.)

Click the !URL for an instance to copy it, then paste it in your home instance search bar to go there and subscribe.

Another useful resource is c/trendingcommunities@feddit.nl - not helpful for searching, but handy to check daily after you’ve built your subscriptions and want to see suggestions for growing communities.

Regular search features are lacking a bit due to the nature of federated servers. Hopefully these features will be added someday. Till then, dedicated sites like lemmyverse seem to be the best option.

You can sort by various metrics and search by keyword at https://lemmyverse.net/communities

I'm with you, the community management aspects of the UI could do with some love.

My quick thoughts:

1. Sorting by the columns in the list of communities page
2. Have the search field not jump to the generic search, but instead apply a filter to the table (which can then also be sorted by the columns)
3. In the Subscribed communities sidebar, also have a search field that alters the list of communities to only those that match the search
4. In the same sidebar, allow users to place communities into folders or lists that can be folded or expanded so that users can easily navigate to user defined subsets of their communities. Currently it's a flat list alphabetically sorted.
5. Either in the side bar or the communities list page, list the number of posts in that community today. I don't know how viable this is, but each community's sidebar shows usage data, including the number of users/day, so something like this must be possible.
6. Much more ambitiously, and it's already in the GitHub issues but I'm mentioning it here anyway, 4 above naturally leads to providing a feed for only a selected user defined folder/group/subset of groups, so that they're not merely for organisational purposes but like multi-reddits a nice way of customising your feed.

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