Well, what i propose is to have a "safe" inventory in Boston, for a fee. And not because i like it...people shouldn't have any way of safe storing things. But as things stand now, there are already two ways to have a "safe storage".
1)Alts
2)Stall - you just have not to set a price or to set an extremely high one - and since it is inherited and the stalls are in limited number, it is a form of storage also limited to the first people who got it, as long as they pay the weekly rent.
So, even if the developers find a way to settle the first problem, there's the second one anyway. So what i propose is having a form of safe storage cheaper than the stalls (so that people won't have to use the stalls as storage, thus permitting other people to use them as intended).
It may be an inventory with a small rent and a fee everytime you use it, for example. Maybe it could start small but could be extendable, something like 25s per slot, so that it starts as a 4*4 inventory and you can extend it to an 8*8 inventory.
Or they could find a way not to have safe storages and to avoid having people use the stalls as a form of storage. And it would be even better...