It is indeed normal that these sell less as people don't need that many personalities. But for me they are among the best sets you've made. So if you need to add older or new sets to make them profitable, the please do.
BTW Napoleons general staff 2 is the only set on my list that I just can't get hold on. And te other sets are also difficult to find. I asked my dealer if that was on purpose, but he set that it was hard to get.
On the Kamrat site they are anouncing a few new BUM sets including a guillotine set, we could argue that tthis is a non military set although it tended to go along with civil unrest and military intervention. we should keep an eye on this et to see how well it sells.