I wouldn't mind a third party Kinect, provided it didn't do anything except sit and tell the Xbox One it was plugged in so that I could play my games without having the real thing watching me all the time. And yes, I know they've said you can turn it off completely. I just don't believe them.
As for third-party game pads, I'm pretty sure they're here to stay. As long as it's possible to make pads which are either cheaper or better quality than the official line, there will always be a market for them. Last generation, there weren't so many third-party controllers purely because it wasn't really possible to improve on the design of the standard Xbox 360 pad. There were, however, quite a few which weren't very good, but were very cheap, and modded controllers with auto-fire and turbo buttons have been just as popular as ever, so I'd expect to see that continue.