I find the 2" M15 a Smith that got almost everything just a little wrong. A short gun with delicate and bulky fully adjustable sights, a difficult to conceal square butt, and too-big-for-38 Special K Frame. If one were to carry this much gun would it not be worth the slight difference in size to upgrade to a 2.5" Model 19 or 3" Model 13? If one must have a small 38 six-shooter then the Model 10 or Colt DS or Diamondback would appeal to me long before the 2" Model 15.
Please do not take this personal....just feel obligated to share a different view and I certainly do not want to degrade this pleasant conversation into an argument.
Your observations certainly make sense, but they don't always work out to the expected conclusion. I'm not sure that the sights are delicate, but they are not as smooth as a M10 or M12 frame, for sure. However, they do not necessarily snag anything in every person's carry mode. I find the high M15 sights quicker to see and quicker to aim with than either of my M12 revolvers (one RB and one SB).
I would prefer a round butt because of my hand size, but Bill Rogers designed an excellent set of grips that are both thinner and longer than factory.
I have a DS and a Cobra, but for some reason, neither is as accurate as the 15, at least in my hands. I have thought about going back to my snubby 19, but at one time I felt that a .357 was improper for my circumstances, and now I'm not sure it is necessary.
The DB (I once had a snubby one) can certainly be shot well, but so can the 15. Your thoughts are, IMO, very much worth considering, but for some reason, the 15 with Rogers grips works out best for me in many circumstances.