[vbat99]

Maybe just have it look for .srt and how many instances rather than which. Bandaid mode.
Then you get in the...looking for .sub or .idx as well. I guess... Call Subtitles = .sub, .idx, .srt and put a count meeting any of the 3 criteria rather than specified file names. It'd probably make someone happy.

There's way cooler things than subtitles

Yep, I understand where your coming from. It's why its lower on my list of things to do.
Currently MC checks for matching ancillary files by the Movie filename, and the extension.
ie:
Avatar.MKV
Avatar.srt
Avatar.nfo
Avatar-poster.jpg (exception for artwork, looks for -poster or -fanart)

And MC looks for these subtitle types.

Code:

{".sub", ".srt", ".smi", ".idx", ".ass", ".ssa"}

Trust me, this is lower on my list, but it will be done.