Instead of just top/middle/bottom, I suggest a finer control where we can move the subtitles up and down in steps (e.g. +/- 10). I’m sure this feature would be greatly appreciated by owners of constant image height screens. Many (UHD) Blu-Ray players such as the Oppo UDP-203/205 support this feature.
Additional thought:
Most subtitles are originally positioned at the bottom, but if there’s already some text in the picture, the subtitles are shown at the top. In order to keep them always visible, I suggest that a positive value shifts the subtitles towards the middle of the screen, and a negative value shifts them away.
There’s already a number of related (but different) suggestions, discussing options to place the subtitles in relation to the video. Those aren’t duplicates, I’m just mentioning them as references.
Thank you @OttoKerner, I think these are viable options for HTPC owners. Right now, I’m using the Plex players on Nvidia Shield TV (2019) and Apple TV 4K, that’s why I would really appreciate it if the Plex team would implement these controls in the player apps.
2024 clean-up: duplicate(s); please comment/vote in the suggestions linked above, aiming for options to place subtitles at the bottom of or below the video.