one thing I'd like to see standard across various federated projects is a small icon and/or text indicating the source project of a post, i.e. Mastodon, Calckey, Misskey, Pixelfed, Peertube, etc.
If the point of the #Fediverse is interoperability, it would make sense to highlight that and sort of make clear what you're seeing in your feed and its source (or what you're seeing in Federated feed where you wouldn't necessarily know the source.)