I think the issue of barrel length is in part dictated by how you shoot at a target, whether clay or feather. If you tend to track a target and manipulate a sight picture before firing, a longer and heavier gun usually suits. If you tend to shoot as Churchill subscribed where you fire when the butt touches your shoulder, then a shorter dynamic gun is usually preferred. Either gun can be effective at either clays or game but the shooter needs to understand the inherit dynamics of the gun to have very much success.
I have only 12 g (or bore) but have barrel lengths from 25” (AYA XXV) to 32” (Blaser F3) with a number of 26, 28 and 30” guns in between. I have shot many at game and most at clays, typically low gun skeet or sporting clays with reasonable success. However, the method to shoot my XXV at skeet to break 22-23 is much different than to shoot the F3. Both work, but I prefer the F3 for clays and the XXV for most game shooting, including high pheasants.
My thoughts
Z