How would that really be any better? Because then for people who store gear or play all jobs or most of them, they'd have to carry the same amount of up to 20 slips instead of 14?

I don't mind that I have to trade 4 slips to gear up a job, to me. Saying that "I'm tired of having to trade so many slips is so awful" is kind of lazy. Considering how much the slips save you in inventory, I'd rather have 80 slips take up one full bag of inventory than to have to try and make due without slips or without more to do things like accept loose abyssean and voidwatch specific gear, and unaugmented relic, and magian weapons.