Nice thread idea, c.sam.
I make a distinction between real trains and my models. Among real locos, my favorites are the bigger the better, Big Boy, Yellowstones, Allegheny. I have models of them and they sit on the shelf mostly, but I love to look at them there.
My favorite articulated toy locomotives are the ones that look good running on my layout: and that means a handsome scale loco with good detail and minimal overhang/jut-out at the front. My JLC BigBoy, Allegheny, the Yellowstones, and even the H7, etc., etc., are nice, and I love 'em, but they look more than a bit unrealistic making their way around 72" and 84" curves.
I love the Vision CC2. It is quite interesting to look at, a very detailed mode with good sound, great runner, etc., and has very little overhang at the front: the two photos below show it on 72" curves.
But my favorite articulated is this Legacy 2-6-6-2 Mallet. It is very handsome, and looks big (because it is) and has reasonable overhang at the front. Here it is on a 72" curve.