If you are comfortable with a revolver then why not go from a S&W 637 to a S&W Model 60 or 640 in .357 magnum? Those keep you in J-Frames.
You could also look for a K-Frame of larger revolver.
Actually I was looking at a Taurus 66 blued 4" that has seven shots yesterday. Almost picked it up but I was gonna trade in the shield and I kinda wanted to have at least one semi auto and Revolver. I reload .38 specials and like the 637 as a pocket gun so decided to wait on another Revolver. Definitely gonna get another wheelie later, but I want to "upgrade" from the shield first. Gotta plan out my collection lol.
I have two jobs so selling this gun has been a *****. Might just end up doing a trade in at the shop instead. First time gunsale nerves I guess.