yeah essentially managing inventory for multiple jobs is a bad deal, and yet the system makes it so you will want/need to level multiple jobs. They actually had this system in place earlier in alpha, but it was insane to try to level multi jobs, and switching fast was horrible.
I dont think this issue should have anything to do with stats, if you mean me, i was refering to the fact that if you equip gear that is under level, or non favored, you suffer a blow to the gains, that makes it even lower than something close to your level. So stat wise, there is no advantage to cross class gearing, in fact i never do it on any job im taking seriously. So this becomes a problem of goals, not really stats.
Also a lot of people do not realize that they are taking a hit to the items base stats, because in the big comparison window, it looks like your gear is better, its only when you look to the actual attributes of your charachter do you see that you arent getting the real stats of the gear you put on. I see people on the forum still saying you get full benefit from higher gear, which is not true.

Basically, i am one of those people who dont really want to spend an insane time managing inventory, or buying gear for every class when im just messing around on it. but there are a lot of people like me, and remember when the game goes live YOU WILL PAY FOR INVENTORY every retainer will cost a dollar. making a system that seems to force you into needing 3 or 4 retainers just sounds like upping the monthly cost by 3 or 4 dollars.

A solution like i suggested, i really dont know how hard it will be to implement, in theory it shouldnt be that hard, the models are already made, and they already have routines that look at your level, job and compare them to the requirements, and then implement a change. If it is super intensive, maybe not, but i think its better than the you need gear for everysingle job you mess around on, remember your supposed to be gathering crafting and doing multiple jobs all the time in thier vision of this game, really look at the amount of inventory youd need for that, its insane.