I carried a 686+ with a 3" bbl for awhile, then went down to a 686 with 2.5" bbl before settling on a Model 66-2 with 2.5" bbl for my primary carry.
My experience was kinda like the story of Goldilocks & the Three Bears, when I got the Model 66 I felt that it was "just right."
Your mileage may vary
Edited to add; For the record, I carry cross-draw.......