I would love to try a Rhino.
If the Python (sweet) and the 686 are in your future, you might not want to add yet another full size, adjustable sight .357. Maybe a fixed sight, 3" GP100 or SP101 for a possible concealment gun would be a change of pace.
Our local IDPA champ shoots a S&W .40 revolver, not the 10mm 610 - I think it's an L frame, with moon clips.
Do you have a good .22lr revolver? I think that might be the only affordable handgun to shoot in the future if we run into gov't interference with our centerfire ammo/guns.