Two guns.
First, I'd like to see an inexpensive, lightweight, small .22lr SAO polymer-framed pistol. Not a mouse gun and not large, like a Mark II, but about the size of a good .380acp. Flawlessly reliable, cock and lock design safety and an easy safety released by a quick downsweep of the thumb. I'd like to see it chamber ten rounds with optional extended mags.
Next gun, a true MEDIUM-frame .357 revolver weighing in around 30 ounces with a 4-inch barrel that would accommodate installable weights. That way, a person need not haul a 44-ounce revolver around while hiking, camping or hunting. The gun also should be ultra-durable, impervious to weather and attractive with or without weights.