With repect to small or natural cell, I have enjoyed Michael Bush's website www.bushfarms.com
. He gives a great explanation of the benefits of natural cell and the process of regression. I am converting my one existing hive to natural cell size and am starting my packages off this year on starter strips of small cell (4.9) right from the git go. This regression process is a bit daunting, especially in deciding when the first round of starter stripped frames need to be culled and to let the bees do another round of regression and the issue of how long I should leave the frames in there once I get them regressed. There has to be a time that a frame should be recycled and to allow the bees to draw fresh comb (but perhaps I am wrong in this assumption).
But to answer your question the other advantage to natural cell size is the lack of need to chemically medicate the bees against mites and creating a hive more likely to survive what is thrown at them. This is, at least, my limited understanding. Intuitively, however, it seems that what the girls want to do naturally is likely best for them and us. Mother nature rarely, if ever, gets it wrong, so I am inclined to allow natural tendencies to control hive construction.