I graduated from a Morse Ceili to a Carroll about 4 years ago. I chose the Noel Hill model....BUT I chose to have my button layout in the same pattern that my Ceili had. This is what Wally refers to as his standard configuration. Noel suggested a slightly different layout, but I liked (and was used to) what I had.
I have taken Noel's summer classes for several years and I had a chance to sample a "Small", a "Standard", and several of the Noel Hill models. I pretty much exclusively play Irish Traditional music.
The Standard was a tad bit heavier, and I think bigger than my Ceili. The Small was VERY nice and responsive, but I have fairly large hands for a woman (also 5' 10") and I have arthritis, so I was worried that my hands/fingers might cramp. Otherwise, I really liked the Small and I agree that the option to have different wood and design options is very nice. They are beautiful instruments.
The NH model just "fit" better for me and it was a very smooth transition from the Ceili to the Carroll.
I've been very pleased with my choice.
I don't think you can go wrong with any of them!