MAYBE you'd at least WANT the extra umph and shot count, but I don't believe anyone in the world NEEDS it for typical shotgun hunting.
Yes, you do get more shot with the 3.5", this means either a bigger spread or more dense pattern.
No, I don't honestly believe that the increased shot is worth the increased recoil, weight, and cost of the 3.5" ammo or guns. I've never felt like I "NEEDED" a 3" gun, let alone needing a 3.5" gun.
Yes, you get more power with the 3.5", theoretically that means you can reach out farther to kill the same bird.
I have no idea where you're getting these facts but about 1/2 of what you have here is not true...
extra "UMPH" what is this?... if you're talking speed your sorely mistaken... the 3½" are loaded slower than the 2¾" and 3" due to the heavier shot load...
bigger spread?... any full choke will put the same percentage of pellets in the same space at the same range irregardless of shot count...
the 3½ was brought out for 2 specific reasons, 1. to allow a heavier shot load for waterfowlers shooting steel... 2. for turkey hunters to carry a heavier shot load... but even that's been proven to be erred thinking, because a lighter faster load kills better at the normal turkey hunting ranges...
"more power with the 3.5", theoretically " must be your theory, and totally unfounded... a denser pattern at lower speeds is all you're getting with a 3½...
if you're going with the Gold, do yourself a favor and get the 3" if you feel you really need a 3½ go to a 10ga and then you'll have a workhorse...