Beemaster is right. Brood must be in the middle of nuc. If you try something elese, bees try to correct it. A little nuc has a problem of temperature.
If you take 3 frames capped brood and they hatch, you get whole box bees. It depends on weather how much nuc can raise brood. When I use now electrical heating that measure of bees have soon whole box full of larvas. If they are with their own, brood area is 1/3. Night temperature limits brood raising. Also extra food limits brood area, if bees must keep warm vain store of honey frames. Pollen they need all the time.
With little nuc under 5 frames it is better to have insulated box. It helps a lot. Also you can make a divided box, that you have two little nucs and separating wall. So they heat each other. I use this way mating nuc. I divide Langstroth in 4 parts, but still they difficulties to keep hive warm.