Yeah they're nuts. Funny thing though: sometimes you need more inputs and outputs than the 6-sides of a drum can provide, at which point the miniature drum is its own limitation.
My mind is trying to figure out how you could add a second drum to get more "faces" to attach conduits to (just like adding additional AE2 Controller blocks). But you'd have to keep the fluid levels equal somehow, which probably isn't as easy as it sounds. You couldn't let the connecting conduit extract too much from one of the drums. Is there such a mechanic to "equalize fluids"?