I like to build round. Figure my main base is one row of blocks bigger then a maproom. I have most all my benches on the first floor with stupid amounts of room. My thralls get to set around on nice chairs in study groups. Second floor i have my dark stuff, slavers bench, greater friendship wheel, golem benches, sorcery bench and sacrificial alter. 3rd floor is the transpatroy stone pad, and magic pad/circle. With plenty of room to land a bat. I do have a 4x4 private room on the first floor, but all benches have plenty of storage. Like almost enough to complain about 
Now I am dedicated to Set, so only do one temple. But I don’t recall seeing any place in game that says you need to do all the gods. Each temple doesn’t need to be that big. My open air temple to set is 2 blocks bigger then the T3 alter base.