Biermann "I never understand why one would have different size boxes & frames, just complicates life"-------- I thought the same thing once.. I used "intuition" to define my standard Langstroth brood chamber, summer and winter, as a Medium + Deep + Medium. Also part of the reason was I had the hardware but could cut it down or build up to a size.
My observations after two years with my standard brood chamber; 1) intuition still tells me the nurse bees and queen like big frames or larger brood areas, 2) makes it easy to move honey frames down to the top medium box, a little harder to the lower medium box. The main brood chamber stays centerd in the Deep and stay "light". 3) I have no reason to change, so it seems.
I can easily store 80 lb. of honey plus bees and brood space in this configuration. The bottom medium is mostly used as a transition area or as a brood area, if needed. The upper medium has remained the honey band with some brood on the central frames. I still like the idea but I also heavily insulate, all year now.