I have a similar set up to you but have the same number of frames in each box.
What I am finding is that the bees always fill the gaps between the top of the frame below and the bottom of the frame above with comb, usually capped drone cells. I remove these to tidy the hive and try to keep comb where is should be.
1) Is this normal?
2) I see this as removing over half of the capped drone, so helping to control varroa?
3) Just a waste of their energy and I wish they wouldn't, much like their enthusiasm for building comb anywhere else, it is more often than not in the wrong place and not in the shape of the frame (bulges out double thickness into the space of the neighboring frame etc)
Hoping I haven't done something stupid in the construction and the spacing is wrong?