If one parent is significantly better off then the other, finances may be an important factor in choosing the child's home. It is your childrens' needs you should consider, not your own. No matter who the kids live with primarily, the other parent can make excellent and important contributions to the child's rearing, no matter where the child actually lives. When I discuss joint custody with my clients, many begin with the idea that the children will live with each parent half of the time. I have seen these kinds of situations approved by courts, but they are not necessarily in the child's best interest.
Small children do better when their lives are consistent.
They are happier when they know when they can expect to eat, go to bed, or who will be getting them up in the morning. They just aren't that flexible. Routine is a prime source of their sense of security, and systematically uprooting them can be confusing, if not downright disruptive. Visitation with younger children should be more frequent, but for shorter periods of time. They really do feel safer sleeping in their own beds at night.