End shake? How much? .001-.002" is normal and allows the cylinder to rotate with cartridges in the chambers. If it is beyond .002", then I would consider it to be sloppy and in need of attention. Shims are the easiest fix for a little too much end shake. Even with the hammer cocked there will still be end shake. Only the old Colt's eliminate cylinder rotation and end shake, but that is with the trigger pulled, the S&W lock work design will not eliminate either with the trigger pulled.
How does the forcing cone look? Sharp entry edge or eroded? How about the recoil plate? Is there an impression from the extractor star or heavy finish wear from case heads pounding against the plate? These can be signs of how much live firing a revolver has seen.