If I vote for a pool with 100,000 votes and a fee of 15% I get anyway more than voting for a pool with 80,000 votes and 0% fee. Is that correct?
No.
Let's say you have 10,000 votes of your own and to round and make it easy........
If you vote for a pool with a now total of 100,000 votes with a fee of 15% then you get (about) 100 sem per day / 10% of votes - 15% fee = 8.5 sem
(Basically a pool gets about 100 sem per day and you would be 10% of them = 10 sem, but pool charges 15%, so you get about 8.5 of those.)
Let's say you have 10,000 votes of your own and to round and make it easy........
If you vote for a pool with a now total of 80,000 votes with a fee of 0% then you get (about) 100 sem per day / 12.5% of votes - 0% fee = 12.5 sem
I think you were trying to figure out something more like....
At what point is it better to take your 10,000 votes to a pool charging a lower fee than a pool charging a high fee.
Most people don't think about it and simply vote for pools with a low fee.
Not a simple answer since there is going to be a curve in that you want the lowest fee while supporting the highest percentage of votes. (0% fee / 100% votes)
So, it's best to own your own validator if you have enough votes while charging yourself a 0% fee.
With (for the example) 10,000 votes, it best to find a low fee (still relatively the most important - currently), while getting into a pool which barely has enough votes to be a validator (like within the top 100 (easy), but better within the first 56 (like being in position 55).
People voting for pool in position 1 are making less than those in position 55 since they have to share the block rewards with far more people even if the pool in 55 charges a higher fee than that of position 1.
Good breakdown, and it gets even more complicated with large amounts of votes since you could split them up in various ways for optimum payouts. Is the the "first 56" positions because the validator rewards are still skewed to benefit the higher positioned validators?
Keep in mind that BTC holders didn't know of the airdrop and I believe the snapshot was taken before the drop was announced. So, no manipulation could be done and if it was, it took a lot of money to make it happen. Dropping to ETH on the same ratio and having given advanced notice means manipulation will take place at a far cheaper cost.
Do we know that BTC holders were not notified ahead of time? I thought people had specifically spread out BTC in addresses for optimum claims... although maybe they had just been lucky enough to have it that way. What details were known before BTC airdrop?