I actually use the bearodactyl suggested setup, but with a single custom folder and symlink the casting huds from /tf/huds to /tf/custom/a_casting_hud, which contains the configs for the cast instead of having to rename/replace custom folder, but that is only useful if you don't play TF2 at and don't have wildly different playing/observing configs.
bearodactylif you wanna go crazy you can also do a symlink for your %APPDATA%\roaming\obs-studio folder so that you can have an entirely different OBS setup (stream keys, plugins, everything) for casting and for regular streaming, may be easier to just use the profiles thing in OBS but if you have all these batch files in one folder you can just double click all the casting related ones and it's super easy, then double click the ones to swap back once you're done
Actually using the existing launch-options to switch profile & scene collection for OBS in a shortcut (or .bat file) make a lot more sense than also starting to symlink there or create custom portable folders for each org/stream.
"%programfiles%/obs-studio\bin\64bit\obs64.exe" --startreplaybuffer --studio-mode --profile TFTV1 --collection TFTV1 --scene Music
And yes, I can confirm the hardest part about producing TF2 streams is team/player cooperation and the actual observing. I've been super spoiled with the ice hockey esports production I've been able to do the past months where the matches won't start until they have green light from production to start the search/match.