Good question brooder, there's a few things to consider. But as a general principle, if honey production is the goal, then transferring brood from strong hives to weak hives is a good idea, the reason being that an apiary as a whole, will make more honey if all the hives are balanced up or equalised, than if there are some big ones and some little ones.
So, how to do it. First thing to consider is if there are weaker hives that need a boost, why are they weak and should resources be used on them. There could be quite a few reasons why they are weak, and if it was due to a disease such as say, mites, adding brood could be a waste of resources unless the mites were dealt with also, by treating the hive. But there could be other reasons for a weak hive such as it was not left with enough feed in fall in which case boosting with some brood is an excellent idea to get it up to par.
Something people often forget is a weak hive, if it has a normal queen, will often have all the brood it's few bees can cover. So simply adding more brood can overstretch what the bees can keep warm & result in dead brood, meaning we do more harm than good. In these situations it is necessary to find the queen in the donor hive so brood, with nurse bees on it, can be given to the other hive. Always give brood that is close as possible to hatching, so there is a smaller time window of risk for brood chilling. If it is known that weather over the next few days will be warm, brood without nurse bees could be given provided it is within a day or two of hatching.
The advantage of "balancing" hives in spring, is that strong hives that are the ones that would be most likely to swarm, are reduced in strength so will go on to make a better honey crop than if they had been allowed to swarm. The weak hives benefit also, and go on to make a better honey crop than if they had not been boosted with some extra bees. So it is win win, and standard procedure in a lot of honey producing commercial apiaries.
Has to be done right though & requires some skill to really do it to best advantage. IE, don't spread disease, although it is mostly not the strong donor hives that have disease but keep disease in mind. Know the weather forecast & other conditions so as not to give weak hives more brood than they can care for. Only give brood very close to hatching. View brood removal from the strong hives as a method of swarm control & attempt to achieve that aim by what you remove, plus how the hive is manipulated such as spreading remaining brood, etc, to ensure full advantage from the time you spend in the hive. Ensure all hives end up with all necessary feed & good potential to go into the honey season in good shape and top honey producers. Do not allow any poor hives or "dinks" as people call them. Fix them, or break them up for nucs, or do something with them, having non productive hives in a yard is sheer waste. Ensure every hive is enabled to produce an excellent honey crop.
That, to me, is one of the big things beekeeping is about, getting the best from ALL our bees not just a few of the best ones. Even though hives are equalized, breeder queens can still be chosen by keeping motes about suitable candidates written on the hive mat.