I don't want to rain on anyone's parade here, but the 225 is the only weight that makes sense. It would be useable in the larger 35's as well, and that means that it might stand a chance of being produced for awhile.
I don't want to rain on your parade either, but I have to totally disagree with you regarding the weight issue.
The .358 Winchester and .350 Remington start suffering as bullets get longer with increased weight and start to intrude further into the cartridge body. There is also the issue that a lot of rifles in these cartridges are built on fairly light rifles, and if a 180 or 200 grain bullet will do everything you need, just why use heavier bullets and incur more recoil?
I will agree with you insofar as most people using .358's seem to think the caliber requires either a 225 or 250 grain bullet. I am at a loss why this is, unless big bears and/or elk and moose at long-ish ranges are on the menu. I have only used the Barnes X in the 180 grain weights, but it knocks down deer and elk with real authority. Nevertheless, if hunters are prejudiced towards the 225 grain offerings, then it does make sense to make what sells the most.
However, I won't be buying any 225 grain accubonds from Nosler or 225 grainers from anybody else. For me, it is neither fish nor fowl. The .358 Winchester and .35 Whelen get the 180 grain treatment (and 200 grainers once those run out); the .358 Norma and .35 Newton get 250 grainers.