Greasy Fork

Have you considered using farside for the various instances?

https://farside.link/

The way it works is that you can just link to, say, http://farside.link/invidious/nintendomaniac64 and it'll automatically redirect to a working invidious instance for the youtube channel "nintendomaniac64"

And this works for all of their various services listed and the like; here's a more simplistic userscript made by someone else which hasn't been updated for almost a year that redirects a subset using farside.link for example:
https://greasyfork.org/en/scripts/441742-farside-redirect

That being said, it'd probably be ideal to retain the existing non-farside method as a fallback solution.

Apparently one cannot delete feedback on here even if it's only been less than 30 minutes since leaving said feedback...

Basically I posted this to the issue tracker on your NotABug git instead:
https://notabug.org/NotYou/open-source-alternatve-redirector/issues/1

@NM64 then what I should do about HyperPipe (Alternative to YouTube music)? Is Farside saves category that use choose for search engine? (because my script does, you can simply search by image in google, and then it will redirect you to SearX search page with images results). What about Language for WikiLess how I should transfer it into farside link?

@NM64 Furthermore to what @NotYou has said, I would like to add the following reason on why not to use Farside and continue with single instances as currently in this script:

Farside redirects to a different (random) instance every time and there is a problem with that

1. Settings have to be reset for every instance. Let's say you have settings saved for the yewtu.be instance of Invidious in your cookies. You have chosen dark mode, player style "Youtube", 1080p as standard video quality etc. All those settings don't get carried over when Farside redirects you to another instance. You would have to reset them in every instance Farside would take you and also add an exception on every new instance for cookies if you block them by default like me.

2. Different instances run on different versions of the respective API. This is the list of Invidious instances. As you can see yewtu.be is on the newest version while some are still on 2022* version numbers. Same is true for the other frontends. reddit.invak.id is running the latest version of libreddit, 0.27.1 released 5 days ago according to their Github. Yet lr.riverside.rocks is still on version 0.15.2. You can see the latter lacking features the former has besides stability fixes etc.

3. Latency. Yewtu.be makes sense to use for European-based users. Their servers are in the Netherlands. But US-based servers will have better latency for people based in the US or even elsewhere in the world. You can easily change the instance in this script to your preferred one while Farside would end up redirecting us to servers with non-optimal latency as well as long as the instance is up and running.

This is why I find his script to be a much better and more advanced alternative to other redirection extensions (Libredirect etc.) and Farside.