also, another mild masto take:

i don't really think the fed timeline as-is is a good idea.

it's a firehose of content from everywhere. yeah, sure, that's great, i guess. but especially on larger instances or more well connected ones, it's a huge blast of stuff that you have no way of controlling.

i don't really have any thoughts on how it could be improved. (maybe an option to choose instances that appear there for yourself?)