Re: Q: How to recombine a queenless nuc?
If your nuc is queenless but not laying workers, then you can just remove 5 frames from the big hive and slip in the frames from the nuc. If it's queenless without laying workers then there will be no, or very little, fighting. I only worry about using newspaper if both hives/nucs are queenright. If one is queenless and no laying workers then I just join them on the fly with no problems.
20+ years, raise my own queens, feed when needed. I treat, but have not perfected varroa management yet.