A PKMN has set IVs once its captured or bred, meaning its IVs will stay bad, they are not changeable.
Where is the strategy in soft resetting or IV breeding, all you do is giving a PKMN a power item and an everstone and then press left and right for hours -.-
Also, by saying it would be all about strategy then, I meant battling not bredding and stuff.
A PKMN can still have different natures and different moves, as well as teammates, if IVs are "removed".
The point is, the IV system has nothing to do with strategy, and even what you're suggesting wont change that. The strategy of the game is elsewhere.