So one of the deal breakers that was preventing me from upgrading to OS X 10.10 is how ugly the dock looked (to me).
Since I had success getting some of the Yosemite's apps up and running on Mavericks (Yosemite's terminal for example, it supports scrolling with trackpad for some cli programs where you normally have to scroll with C-n, C-p or directional keys), naturally I tried the opposite, i.e. running Mavericks' Dock.app on Yosemite. Surprisingly, it worked! At least, partially. Functionality-wise, it works just fine, but on the looks it is missing the background image of the Mavericks' Dock.app.
Can someone more knowledgeable figure out a way to make this work 100%? As far as I know I'm not the only person wishing for this to work so if you can figure this out, you're doing us, a portion of the Mac community a big favor!