Great metaphor, and interesting proposal. I like it on the surface, but let's try to dig a bit deeper here in the comments, shall we?
In fact @dan, @ned and the other devs did take content discovery into consideration which is why rewards are higher for curators who vote earlier (as in, before other voters and outside of the 30 minute grace period) during a post's lifetime. However, as you've pointed out perhaps that's not enough.
There is an issue here, however, with your implementation. You would be helping the "rich get richer" as they say, and making it harder for the unknown, "poor" folk to get ahead.
I say this because you don't just take away rewards, since all rewards are cut out of a certain pool. If you're giving less rewards to the curator, you'd be giving more to the well-known content creator. If you increase rewards to the curators, you're taking away more from the unknown content creator.
So there's still more to hash out here before I think this proposal is ready to be considered fully.
It totally make sense though, because for the unknown poster, what they need is discovery, not an immediate pay out. In exchange for some of the payout, they get to be discovered. This is actually a really good deal for them.
Where as for already well established posters, why do they need to give curators so much of the pie? They don't really need curators' help. So, they should get a bigger share.