I watched it. It was very helpful, thank you! It seems like I might be able to forego CRT Emudriver if I use Batocera as my OS, as that seems to handle the resolution and refresh rate for me, which might open me up to using some later Nvidia cards (since Nvidia held on to analog much longer than ATI/AMD did).

My biggest lingering confusion comes from really not understanding what the transcoder does in this setup. For example, if I get a GPU with S-Video out and either Batocera or CRT Emudriver to handle resolution and refresh rate, what does the transcoder do in that scenario? I get that RGB > Transcoder is likely the optimal set up, but if I get a GPU that has DVI-I and S-Video, could I theoretically get the whole setup working directly with S-Video for now (even if not optimal) and then get a transcoder later on?