Now that we have movie versions implemented, hopefully we can discuss the issue of trailer versions.
I collect trailers, for a given movie I can have three or more trailers. Trailer #1, Trailer #2, Teaser Trailer, TV Spot, etc. Sometimes I have obscure things like 35mm trailer scans.
I am sure I am not the only person who collects trailers since many Kodi users are movie enthusiasts and collectors.
Kodi does not have any way to choose and view multiple local trailers.
In addition it is important for some of us to preserve the type & provenance of each trailer in its filename. For example:
Jurassic.Park.1993.Trailer.2160p.35mm.Scope.mp4
Renaming to <moviefile>-trailer is not ideal because then we lose the details of each trailer, what it is and where it came from.
I would propose that anything in a trailer subfolder is treated as a trailer, regardless of the filename. And the GUI allows the user to name the trailer version in much the same way that we can now name the movie version. There could be some default choices like Trailer#1, Trailer #2 and the user could type his own name if the default ones do not suffice.