Sage, Rocky...I like the way you think. We really do make things too complicated, sometimes, but you just dumbed it down perfectly! You could set up three or four baskets and sort the brass for virtually every cartridge chambered in a shoulder-mounted rifle, into the categories you listed above. Only difference would be bullet weight.

As Mike already pointed out, if you've got a high scope mount, like one of those shoot-through models with very high rings, your bullet has climbed more to get to line of sight at 100 yards, so it won't drop off as much as the tables suggested they will. Those are just for reference anyway. You can handload, chronograph, calculate your own BC, etc...until you actually SHOOT at longer ranges, you won't know what your gun/load does.

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"For my part, I prefer a sensible median between trying to shoot an animal across a township and getting close enough to ram the rifle muzzle down its throat." - Jack O'Connor