I say speed kills. Everything I shoot is 1500fps+. Early duck season 7/8 oz 3s, smaller ducks in the decoys. When goose season opens, I shoot 1 1/8 oz BB as a comprimise. When only goose season is open, September, and January through march, the 12ga goes back in the cabinet, and the 10ga with 1 3/8 oz T shot comes out. I also don't have to make adjustments in lead, as all the loads are traveling at about the same speed.
This also saves confusion of what's in a shotshell. If it's 2 7/8, it's the early season 7/8 oz #3, 3 inch is 1 1/8oz BB, 10ga it's T shot, unless it's a federal case, then it's lead #4 buck for coyotes.