Why would Win64 break your T.V. tuner? I know it was a little harder to get my shitty T.V. Tuner working on X64 (getting drivers, at least,) but it was possible. Do you have a crappy generic T.V. tuner?
As for scanners, printers, etc: I really don't believe that it's impossible to get the working in x64 unless they're ancient. Either way, if you want to stick with 32bit and you get enough performance for what you're doing, just stay with it. The last version of x86 Dolphin is functional as far as I can tell with none of the crash bugs that had been plaguing hundreds of releases. I think you need to weigh your own needs and wants in the end.
As for scanners, printers, etc: I really don't believe that it's impossible to get the working in x64 unless they're ancient. Either way, if you want to stick with 32bit and you get enough performance for what you're doing, just stay with it. The last version of x86 Dolphin is functional as far as I can tell with none of the crash bugs that had been plaguing hundreds of releases. I think you need to weigh your own needs and wants in the end.