idea for the future, possible to make a even bigger store? like a massive Ware house, cause i can never have enough (other modes i have have 200 more store lots but nothing like your logistics)
so the idea is changing the two building size and adding a 3rd building
warehouse 6x6 >4x4 (storage the same)
storehouse 4x4>2x2 (storage the same)
new building - underground Supple house 6x6 (3200 or even 4000)
_idea solely, i don't expect you do do this, just a idea

A very late reply, but leaving it here for the future viewers and for the sake of completion.
While I'm partial to the idea of creating a higher-tier, underground storage building... This should be obvious, but changing the sizes of the existing buildings would introduce a LOT of gamebreaking backwards incompatibility - any design that uses ware-/storehouses would effectively have to be redone from scratch. I'm not a dev of this mod, but I am quite confident they do NOT want for this to happen.
So. :o