Fabric Server Mods / General Noob Questions

Was following the Fabric/Quilt server optimization guide and have questions about the mods listed and some general Fabric server questions.

First off is ScalableLux a good replacement for Starlight?

I was reading on what Carpet does but I am still not sure if it changes vanilla mechanics and/or what its purpose really is. My server is semi-vanilla with not very many non optimization mods so I don’t know whether it is something that would be useful to me and my players or not.

My host is Modrinth and when I added Fabric Language Kotlin so that I could use Ledger it added the newest version of the mod but then when I added Ledger it automatically added an older version of Fabric Language Kotlin so now there are two versions of the mod on my server. Is this normal/necessary because of Ledger?

Modrinth also automatically added Bukkit4Fabric to the server. Does Modrinth automatically add dependency mods to the server when it recognizes that they are needed? This would make sense but it looks like all of my mods are Fabric mods so I am not sure why it added Bukkit4Fabric unless the purpose of that mod is different than what it said when I googled what it is supposed to do.

Last thing is that I am not sure what render distance, simulation distance, and map size most people set their servers to but if anyone could let me know what is best practice I would appreciate it. The guide also suggests that I change the sync-chunk-write to false and max-chained-neighbor-updates to 10000, let me know of that is something I should still be doing because the guide is a few years old so I am not sure (some of the mods it suggested are no longer needed so that is the only reason I question it).

Please let me know any information that I need to give for you to be able to answer these questions because I assume more info is needed I just do not know what.