Ok,
I'll bite.
You just named my three favorites! I do prefer the .36, either the '51 or '61 just for it's inherent pointability and accuracy, but for sheer power and beauty my '60 Army is right there on top. Mine is a fluted 2nd Generation but I don't shoot with the fluted cylinder (leave that aside for aesthetic reasons) instead I use a spare rebated cylinder and love the looks of that as well. Possibly moreso than the fluted.
The Navies....
The 1860 Army with the fluted cylinder...
Army with the rebated cylinder next to it's "younger" cousin.