If the game is well designed shouldn't be a "more efficient player" in all situations and tactics.
In the case you say, the perimeter player, even playing an inside oriented tactic, will take more outside shots than inside shots. And he doesn't need the 20 IS to make most of the inside shots against perimeter defenders. So I would take the extra JR if I can pay it.
The difference with the recent change in the game engine is that, before the change, some teams "tanked" the outside shots. You could see teams winning the game with a 0% or 10% in 3pt shots because they relied only on the inside shots to win the games. So they didn't need the JR at all. Now with percentages in inside shots going down, I guess you need a more diversified offense.