Star trades are a loophole BB has not been happy about but has increasingly acknowledged in recent years as a given. Making star storage "official" would take the benefit of having a lot of storage away, so how about this:
BB adds a mechanism to send excess storage/production to your star menu but adds a time-delay to it (e.g. 2h). The idea is to create enough of a disincentive to make people keep normal storage high but eliminating much of the need for star trades, mail storage and other "cheats". What do you think about that, folks?