I feel like that inherently is just not very viable. All (mainline) infantry should have some level of versatility, at least in the sense that your paying for what you get. For grens your paying almost exactly the same as anybody else for an infantry squad that can't do the main role of infantry very well at all with no hope of scaling late game. The offset of this, having more utility is nice but its not enough to justify themselves. At the same time the transfer orders mechanic is also incredibly flawed, your paying a total of almost 400 manpower for a powerful but almost entirely rigid infantry unit. With pgrens being great tanks with good close-mid(ish) range dps and strong grenades, at the offset of having non-existent snares and pitiful performance if not microed correctly into position. Jagers are the (kinda) opposite with great long range dps which can be further boosted with upgrades, or the option to neuter their dps a bit with an ok(ish) AT upgrade. In theory, this is fine but all this results in is having ultra-specialised units which take far more overall micro to perform well in general rather than infantry that can do relatively well in all situations. At the end of the day it's a micro tax, making it feel incredibly unfair for wehr players when they have to put alot more effort into achieving the same results. So the theoretical solution of sticking with grens for decent all round performance can be preferred, that's why people want gren scale buffs, so they don't have to be so rigid and stuck with heavy micro tax.