Ideally the best is to be in the first 5 upvotes after the 30 minutes for maximum rewards.
Either I don't understand you or this is incorrect. In case there are already quite a few upvotes within the 30 minutes, you will basically get no curation reward.
The same goes if a whale upvoted before you. And neither will you get any curation reward of no one upvotes after you.
Then you created sort of a table that states of Steemonians with equal SP upvote the first one gets $1 and the second upvoter gets $0.90. This also seems incorrect as the second upvoter gets less then half of the reward from the first upvoter.