If all you're looking to do is nicer input switching, a KVM switch would be a better solve.
Capture cards would be more useful if you wanted to record the gaming sessions. AFAIK they will always introduce latency as they are usually designed for a situation where that is fine.
Nice try but I'm keeping my even more instant instant noodles to myself.
I'll give you a hint though, the secret is in being ok with pumping boiling water into your stomach.