I think we all agree that proof of stake is basically only a "solution" because we don't have any way to guarantee one person one vote reasonably. And even using KYC the way Voice does it will eventually fail because one person can create only one account buy can control arbitrarily many. Nothing stops me from paying a million people 10 minutes of their time to go through the KYC of Voice and give me their access.

So, what it leaves us with is some sort of balanced stake based voting.
Now, the problem is from the game theory aspect there are two things at play:

• My direct rewards
• My rewards from the growth of the value of my stake due to the growth of the platform.

Before the last HF we saw pretty much where it leads us:

• My direct rewards is the determination for 90% of the stake

Even in such a way that people deemed the platform as broken.
If we take what you suggested, and I can just give myself 1 upvote a month with 100% of my own stake, and there are no downvotes to prevent this from happening would quite definitely mean the death of the inflation based reward mechanism of Steem.

There is no reason whatsoever to vote for someone else (Besides the benefit of the platform, but we know that almost no one cares about this).

Now, you are right, if we calculate every 7 day the split, that'd be an easy way to calculate the share nicely. But, the problem is that every vote I give, the interfaces will have to update the value of all posts I voted for already (bad overhead).
While this is not that bad, I wouldn't like it personally, I think especially when you got a big stake to upvote, you might want to give different values to different posts.

But, for me this would definitely be something to have for the "smaller stakeholders" who don't care too much and just want to use the platform. Maybe a secondary system where you can choose "weight: dynamic" and one where you assign it specifically.

Game theory based you could make dynamic the default so most people would just go with this.

Still, it doesn't fix the problem of:
a) Distributing Steem to as many people as possible to decentralize it
b) The problem of everyone just selfvoting
c) Grow this platform (Directly related to b)

I think the current system does a reasonable better job at A to C than the previous setup but still doesn't do a very good job at making people understand that downvotes are not mobbing but are a way to balance the payouts people get for the sake of the platform.

Which would be solved by my proposal.