Well, just give us opportunities of all kinds to build any size inventory. Perhaps a legendary could come with a new inventory page code.I definitely don't think they should be lootable, but having them as quest items seems interesting. I still think paying a large amount of gold for them is the best idea.
Personally, I wish the devs would fix or upgrade the selling mechanics. There is no conceivable reason I can imagine to make us pick one item at a time to sell. And not when the very same function exists on the sellers window to RETURN your item instantly. At the very very least, one click and the item should jump to the next available seller window spot. Jeez.