It varies from team to team; I mean, my PG's have the most OD, followed by SG's, then my SF's and Pf's have about the same OD, heaven knows why, and Centers the least. I've seen teams where the Sg's have more than Pg's, and teams where the SF's far outmatch the rest of the team, and have better OD. It just depends on the team.
If you asked me, I'd say that in a Run and Gun offense with the same matchups at every position, the Shooting Guards would take a couple more shots than the Point Guards, and the Small Forwards would have the least shots. But that's just an assumption from what I've seen.