Love a stand mixer and believe in the grinder attachment as long as everything is kept very cold during grinding. Prevents the blades from "tearing" the meat rather than mincing. Sausage stuffer on the other hand can give inconsistent results...often tougher to produce good sausage than it's worth due to it's top location and awkward control of the stuffing speed. Spend a few bucks and get the "crank-style" stuffer.
I feel the same about the pasta attachment. In my opinion, the stand mixer is fine without trying to replace everything in the kitchen with it.
On the other hand, I have seen some strange homemade gadgets operating on a Kitchen Aid that looked quite effective...I accidentally stumbled onto photos of those while searching for music by "Brazilian Girls." :-/
I also love my new Le Creuset Tagine that my girlfriend gifted on my birthday. And of course the Weber Kettle grill.