Excellent work sir, I've been waiting for Liquid Manager-based storage systems to take off and for someone else to try something with them. Right now, I am using this:
Input on one side and output on the other, with tesseracts on bottom.
Hmm... If you're storing one liquid, can you just combine the ins and outs? That is, have the bottom layer just be liquiducts? The following seems to work (placing a Liquid Manager off the output causes the first Liquid Manager to drain):
So if you have a layered system like this (this is the best I could come up with that wasn't based on your designs, 12 Liquid Managers in a 6x6 area, not more efficient than your 7x7 one, couldn't come up with anything with more in a smaller space [EDIT: I guess I could add four more, one in each of the corners, for 16 in a 6x6 space]):
...could you just have the bottom layer be just liquiducts/redstone with tesseracts out front?