initial distribution on the unspent transaction outputs in the Bitcoin block-chain that are, say, less than 2 years old. The main reason being, you want the new coins to be held by people who are reasonably active in the Bitcoin community, in the hope that they will also be active in the new altcoin community. Satoshi would be excluded, not because he is too rich, but because he's too inactive. Arguably there is no need to reward the earliest adopters of Bitcoin because they are not early adopters of the altcoin. You would advertise the snapshot date in advance, so that whales that were still active and monitoring the scene would be able to transfer their bitcoins to themselves to freshen their transaction dates before the snapshot.

Also, do you see what a leap it is from "whales are dangerous to our new currency because they could crash it by dumping their coins, so perhaps we should exclude them to reduce that danger", and "we should exclude whales because they don't deserve to be rich, because they didn't work for their money"? The first is pragmatic. The second is philosophical/moral; the politics of envy.