I really think you're overestimating how much extra inventory will be needed in SB. Unless you're the type that does stuff like hang on to every dungeon drop for glamour or something, you really don't need all that much space. Even for crafting you only really need to hang on to what you use commonly, which you can likely do with one retainer. If you don't anticipate needing to use it in, say, a week, just chuck it on the MB and buy/farm it when you DO need it.

Also, I had a chuckle at the 1.0 gathering comment. I don't know if you actually did gathering in 1.0, but it actually gave a TON of materials with each swing. Also, if getting so much stuff when gathering is such a HUGE burden on your inventory, there's an easy solution... SELL IT.