Jenise,
To belabor the obvious, some years ago I came to the defense of Bill Spohn's cellar inventory elsewhere with a formula for the optimal cellar size. You start with how many bottles per week you tend to pull from the cellar on average (C) and how old, on average, you like your wines (A). The formula is that you need a cellar size of 50*C*A to maintain a steady-state population and you need to purchase 50*C ageworthy bottles per year. Simple, innit?
To take an example, let's say that on an average week you'll pull 2 bottles from your cellar (supplementing that with near-term drinking wines on other days) but that you have once-monthly dinner parties at which you'll open a dozen from the cellar. Your value for C would therefore be 5 (2+12/4). If you like your Bordeaux and Nebbiolo at age 15-25, your Cal Cabs at 15, your Burgundy at 15 and your Riesling Auselesen at 15 and your cellar is 40% Bordeaux, 10% Nebbiolo, 10% Cal Cab, 30% Burgundy and 10% Riesling, your value of A would be 17.5 (20*0.5 + 15*0.5), so your optimal cellar size would be 50*5*17.5 = 4375 (!!) and you'd need to purchase 250 bottles per year.
It's an awesome burden for a conscientious winegeek, but I know that you're up to the challenge, Jenise!
Mark Lipton