I thought it would be nice if knights could earn tier clearance without having to craft a high level shield. This really hurts sometimes, especially bombers and gunners, who don't rely on it. I think to have an alternative, say having 2 tier 4 weapons, instead of tier 4 shield and tier 4 weapon, to earn it would be nice.
I am a 3&4 star equipment gunner and I use my Heavy Plateshield all the time when I'm in a tight spot, especially when gremlins, mecha knights and greavers get too close, or I need to outgun a gun puppy without any cover or dodging space. Your shield is one of your most valuable assets, even if you are a gunner (not too sure about a bomber, but I'm sure they could probably benefit equally from it) and that's mentioned in the Shieldbearers Guide on the wiki, so i dont see what the issue is.