IMHO it never hurts to have two camera bodies that accept the same lenses and accessories. After more than 52 years as a serious amateur, life has taught me that the Kelly's Law is viable. What is Kelly's law? It is simply the affirmation that Murphy was a blinking optimist! At the present I am liquidating all of my equipment except for my D200, a F100, and an ancient range finder plus a couple of lenses for each one. Yes two film and one digital, but that is what I use and that is what I will keep.
Another observation is that if you sell the D200 and should, at some future date, decide that it was a mistake, you will not be able to find another in as good as shape or for the low price at which you sold yours. By all means keep them both.
Papa Smurf says that life is uncertain, eat dessert first!