Depends how you're playing them. If you're injecting them to use the Gamepad, no. If you're actually booting into the vWii and using a frontend loader (USBLoaderGX or WiiFlow Lite), you can disable deflicker and a few other options to make it look much cleaner. See here:
https://gbatemp.net/threads/wii-output-is-fixed-hooray.628514/
I can answer that. My Wii games are injected for convenience and my eyesight is bad enough that I no longer care if it’s as sharp and clear as it can be. If I can see it I’m happy.It looks very interesting!
Not sure what to do with the resolution though. Because apparently there's homebrew to make the vWii resolution 4:3 without affecting the Wii U's settings. That seems interesting, but I find it a bit unclear how to set it up and I don't see something like a settings menu where you can, when on the system instead of your PC, pick a resolution and aspect ratio of choice for the vWii.