Best Dock Setup w/iMac, MB Air

I currently have an iMac 21" that I would like to use at home with my MB Air. I realize there's the possibility of using a thunderbolt cable to use the iMac as my screen when connected to my mackbook air, however, with a bluetooth mouse and a wired keyboard, I'm forced to reconnect my mouse to the MB Air each time I want to use the iMac as my screen.

Essentially, I want to be able to use my iMac both as a family computer, which it currently does, and also as a secondary screen for my MB Air whenever I connect the two. I just don't want to have two mouses and two keyboards. I'm looking at possibly using a dock instead but realize now that I would still run into the same issue unless I get a wired mouse to keep it connected to the dock at all times.

What do you guys recommend in terms of setup here? Ideally, I would love to use both screens (MB Air and iMac) with my MB AIR being the primary computer since that's where I keep everything for my business. I already own a docking station at the office but looking for a solution that will work at home given it's an iMac and not simply just a monitor I'm connecting to.

Any ideas/suggestions?

Thanks