I used to share media on PC through Plex server and use Plex client on TV. As you mentioned, the quality was not very good. Maybe because of 2.4 GHz wifi. Then started sharing media on PC and play it through VLC. I don't think that is streaming, perhaps " remote drive " or " network drive " as the source. I am no good at terminology, so I could be wrong.
I am not sure I have ever heard of a " Kodi Server ". Links to it please.
Also, in the end, I decided the best way to handle media is to use a Pen drive and plug it on TV. Much easier for me that way.
To d/l subtitles for movies where subtitles are not available.
Does Kodi have a plugin for that ? Which source does it use ?