Rohrbaugh seems to me to be in the business of making pistols for self defense, and not for "training". I can't see them making a pistol in .22 caliber, as I know a .22 can stop a threat, its certainly a really poor choice for it. I think it would be silly to make a .22, and if they did they would most likely lose money on the venture.
I think a .380 caliber pistol being the same size/weight of the R9 would do better in sales/usefullness, if it were designed to be smaller and lighter. But it would be a decent pistol even if they kept it the same size, the NAA .380 sells and that thing unloaded weighs 18 ozs.
Also all steel??? Again the R9 was designed from step 1 to be a compact, cocealable, powerful pistol, and I think Rourbaugh will continue with making this style of pistol. If you make it all steel, it makes the gun much more heavy and less concealable. The seecamp for being tiny in size is a good example because even though 11.5 ozs isn't very heavy in general, for its small size it is heavy.