Much of this is going to be dependent on how one accepts Scrooge's transformation. Essentially, Scrooge transforms to realize that the more meaningful aspects of existence lie in that which cannot be measured and accounted for. As Scrooge changes, it brings forth the idea that what is meaningful lies beyond objectification and quantification. If one accepts Scrooge's transformation, then one accepts this premise in Dickens' work.
I think that Dickens is also suggesting that life should be one in which the important things in life cannot be measured. Dickens is aware that many individuals in London at the time are like Scrooge in that they value money and wealth over other elements of being. Consider that Dickens is writing at a time of mass industrialiation, lack of government regulation, child labor, and Debtor's Prison. These realities all indicate that the way life is constructed is one in which institutions and society tends to value the essential elements in life as objects, elements that can be quantified. Through Scrooge's change at the end of the work, Dickens is trying to show that the important things in life cannot and should not be measured. Dickens is trying to show how life should be in the valuing of human life, emotions, and community. When Scrooge sees Belle as happy and content, it is a reminder that Dickens believes the way for human happiness lies outside of that which is quantified through objects and material gain. It is a reminder to the reader at a point when reality was seen as quite the opposite that the important things in life cannot be measured.