I'm not necessarily arguing against an expansion to the armory chest, since it's not like it's a bad thing, but I have never understood this complaint. There are 29 classes in the game, and 35 slots in the armory chest. Even if you had every class at such varying levels that you needed a separate piece of gear for every job, you have enough slots, with a couple extra for you when you get replacements. (The only exception to this is rings, which I agree was a silly oversight.)

Make sure all of your classes have a gearset assigned and managing your armory chest is not nearly as hard as it seems. All you have to do is stop once in a while and clean out everything that doesn't have a page icon on it. Maybe keep a piece or two in advance for leveling up, but ultimately you can also store that on a retainer as well until you're at the right level.