However, the size I do not see as a defect. Because both cats are capable of - and love - in shoeboxes, offered a few more days to play after shopping, squeeze in. So the size of the cave for me is not important. This is also much bigger than a shoebox, who cares so.
The 10-year female cat takes no love the wide deck area, because they can sleep sprawled there. The upper, smaller (only seat) area is mostly used as a springboard for a loved one serving hatch to the kitchen.
The scratching post is frequently chosen by both as a sleeping place. But is scraped on to the couch - probably because of the wrong education :-)
Advantage is the wide base plate, which gives the tree the required stability when the 2 back to the best - arguing berth - single.