Well, we lost a member from when the prices were set before, so first should at least go down to compensate. And for a deep league, if you only paid the top couple spots while teams might fight more for them, you might also get more teams quitting with a real uphill battle to get to the money. But obviously winning is big, although even dropping to 400 for the winner is still 55% of the pot.
I like the idea of 4th getting their money back. There's no playoffs in the league, but if there were, that's kind of your playoff bonus. If you start with that, then to make enough gap to 3rd, you set that at 80 makes sense. Yeah, we want teams battling for the top, but nothing wrong with rewarding teams who battle it up to 4th place too. If you only pay out the top couple places then a lot of teams might be pretty far from the money only a month or two into the season.
That leaves an even 600 between first and second, so either you split that 400-200 or 420-180. As I said before, probably going 420-180 makes more sense, since it's still a good haul for the top team and not down too much from the old pro-rated amount, but each of the top spots is still more than double the next.
But I also don't really care to argue over 20 bucks here or there too much. If we can't agree, then probably just rounding off last year's payouts makes sense. That would be something like 430-160-90-40. I don't really know if an extra 20 or 40 bucks for 2nd place is going to make teams fight harder for that spot than they already do.