Just off the top of my head...
Bring back the no-dash 640 (stainless steel .38) with the 340M&P sights (U-notch rear with XS Big Dot tritium front), a carry bevel package (including radiusing the edges and corners of the trigger), chamfered chamber mouths, and no internal lock or MIM parts. Duty/carry trigger job with full-power springs. Finished in a satin black DLC coating, like Ion Bond. Custom-fitted Spegel presentation grade smooth cocobolo Centennial boot grips.
I'd also like to see a no-lock, non-MIM 396 Night Guard with a 3" barrel, finished in a satin black DLC coating like Ion Bond, and custom-fitted with a set of Ahrends smooth boot grips in tung oil-finished maple. It will also have a duty/carry trigger job with full-power springs, chamfered chamber mouths and a carry bevel package like the 640 mentioned above. It would have a bobbed/DAO hammer.
I'd finish off with a new take on the 2" Model 12. It would, of course, be no-lock and non-MIM, with a +P-rated alloy frame (like the current 642/442). It would be a round-butt model with the same features as the 640 mentioned above. It would also be manufactured to standard K-frame specs for parts interchangeability. It would be fitted with Ahrends grips like the 396 mentioned above. It would also have a bobbed/DAO hammer.
One more...
An authentic .44 Hand Ejector 3rd Model, nickel-plated. It will be fitted with ivory grips (or a high-quality synthetic substitute) scrimshawed with the number "13" on one side and a black cat on the other. It will be the Jelly Bryce model.