You have asked a very hard question.
My best Hunting Revolver is a 9.5" Target Grey Super RedHawk in 480 Ruger with a 30mm UltraDot on a Weigand Combat Base.
My #1 Grail Revolver is a S&W Custom Shop DAO 66-2 with 3" Barrel.
My #2 Grail Revolver is a 3" Barrel 6 Shot 686-4, I finally gave up on it when I purchased a 3" GP100 with Adjustable Sights. Way less $$$.
I have 2 ICORE/Defensive Pistol revolvers. The first is a 4" Barrel 686-5 with a Fiber Optic front sight built by Ron Power. My other is a 6" GP100 also with a Fiber Optic front sight. So far I have done all the work on it myself.
One I really would like to have back was a 25-2 S&W that I had my gunsmith buddy install a 4" S&W 25-5 barrel on. Making it into a copy of the rare 4" barrel 25-2 with Red Ramp front sight, that is almost impossible to come up with. I am almost sure I had it located on S&W Forum a few years ago. The current owner thought it was factory, and quit answering my questions about it. I made a serious mistake pricing it way to high to a fellow who pulled out a roll of $100 bills, and hauled off a revolver that I had no intentions of selling. A valueable and painful lesson was learned that day. Do not price something you do not want to sell.
I could go on and on 4" 629 No Dash, Lue Horton 3" 24, etc, etc.
It is really hard to just pick one as an all time favorite revolver.
Bob R