The Armoury Chest gets very congested as you unlock and level up all the different available jobs, the armour slots aren't too problematic since multiple jobs can use the same items unless you have multiple jobs spread over a large level range, but since the Job system is based around swapping the Main Hand weapon, you effectively need to have at least one of every weapon/tool type to have access to every job.

Currently there are 20 DoW/DoM and 11 DoH/DoL for a total of 31, and 2 more confirmed combat jobs coming in Endwalker bringing it to 33, with a capacity of 35 that only leaves 2 spare slots new items while leveling one or more jobs.

Ideally what I would like to see is the current Main Hand tab split into two: Main Hand Weapons and Main Hand Tools, not only would that give plenty of spare slots for each category, but would also keep the weapons and tools neatly separated.