One thing to consider is Harry needs to keep maintaining his gear in the Earth realm. Every new sunset degrades magical energies. However Jim has said that all the members of the Senior Council have their own private pockets in the NeverNever... He didn't use the words "private pockets".. The word sounded like Demazeen or something similar, I looked it up at the time and it meant something like "domain" but I haven't been able to find the exact spelling since then and can't remember the word. Demazeen, Demazin, something like that. Could it have been Denizen? When Jim said it it didn't sound like that, more like Denizeen but that could be it maybe
Anyways if Harry began stashing gear in the NeverNever it may not degrade as quickly which means he could make more magical stuff.