It doesn't have a speedometer function, but I selfhost Owntracks for personal location tracking with my Android smartphone.
It has a back end that an android app sends location too, and a front end that displays those location points over a map. It can display lines between consecutive points, show a heatmap of the location points, filter location history within windows of time,, and more.
I can only really speak to your first point. When imported my existing library, I did it using Sonarr/Radarr as applicable. They have a manual import method, here's a description of Sonarr's.
Unfortunately that'll probably work best if they're formatted in a way Sonarr can readily recognize, something like /Season ##/S##E## - .ext. It may take a little work to get there, I found a program called mmv which helps out a lot. It allows you to move files that match a pattern, capture parts of pattern, and use that captured part to name the output file. That allowed me for format entire seasons at a time, but that method does rely on most files having similar names to begin with.
Since Jellyfin v10.6.0, it's had a feature called SyncPlay allowing multiple users to watch the same thing at the same time (coordinates pauses, fast forwarding/rewinding, and all that between clients). I've used it and it worked like a charm, although I did find that not all clients support it.
I doubt Reddit builds a decent search engine, that doesn't actually help them at all.
If users can search, they find a previous post pertaining to what they want to see/know and they move on.
If there's no search, users can't find old posts or comments so they make new posts about a previously posted topic and more comments are made as other users react. That's more content, even if low quality from a user perspective, that shows engagement which can be sold to advertisers.
That's before considering the engineering effort it takes to make a good search engine, constantly fine tune that algorithm, and try to outpace those that are trying to game the search algorithm.
I like Czkawka for detecting and handling duplicate files, similar files, empty directories, and more.
It does get disabled to the Quarterback, however I believe the Head Coach can flip between channels to talk to Offensive and/or Defensive coordinators during the play.