I am no expert but everything sounds great and I would not change a thing. Some races (crosses) of bees do overwinter on fewer stores than others. I have heard that sometimes a mild winter can cause a colony to consume more stores because they can break from their cluster, fly some, and consume more energy. The size of the winter cluster has a lot to do with the amount of stores consumed also.
If that swarm got you surplus honey when you only had them since Memorial day, they overwintered on few stores, and IF they seem to cope with mites well then I would think about starting a few nucs and raising some more queens. That sounds like very good stock!
If that swarm got you surplus honey when you only had them since Memorial day, they overwintered on few stores, and IF they seem to cope with mites well then I would think about starting a few nucs and raising some more queens. That sounds like very good stock!