Hi,
I agree on the giving up on standardizing. While it is certainly possible to get close, when I look for equipment I try to find the best I can afford. In doing so, I too wind up having to have different sizes. I've found (like you) that I can get it down to the three types you've mentioned (plus coin cell for Photon). I guess by making that type of choice, I'm putting what I (and perhaps you) feel is a priority (just my personal choice) on the benefit of the quality of equipment over the need to strive for single-size on the battery front.
One other thought -- for me redundancy is part of the formula, so while my personal carry items and BOB may need a few different sizes, I do try to keep the items for the kits for my wife and children down to 'AA' and 'AAA' items. That seems to work pretty well, and I stock up when I can find items on sale. Just a few weeks ago, I picked up two, 36 or 48 (can't remember off-hand) packs of Energizer Alkalines for under $10 each at Lowes.
Thanks for the battery case and organization links.
Michael
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