It's easier to train inside players, this is not much of a surprise.
We can prob play a center at PF if that center has some outside shooting ability. In base offense, the PF might put up a couple three's on average from my experience.
I've found PFs as well (unless the BP on them is off), so we really aren't hurting for inside positions. This is likely due to your point about ease of training.
But there must be a decent PG
somewhere, since I found a highly skilled SF, and SF is the hardest position of all to train...