Hi Piotr,

Dash has had a fund almost from the beginning, how it works is someone submits a proposal and then all the masternode stakeholders vote on whether to accept it, I don't know the exact mechanics but that is the broad overview, the funds come from the chain and the same as SPS on Steem the funds will come from inflation and not from donation, although I think people can donate to increase the fund.

The 15 min vote window was meant to allow users time to read and vote posts before automated votes managed to vote first, that was more important when there was only a little content, but now there is lots of content that goes uncurated so if a bot votes first, you can easily find something else to vote. The 15 min window was too long for reader to wait to get their full rewards and people move on, the world is too fast paced for a 15 in delay, 5 mins should be fine for blog format, but if Steem content goes in the direction of micro-content like twitter then that window may need to be even shorter.

Yes the bots who have delegation will earn more, but I think people will stop delegating directly to the bots and start curating more themselves or join curation guilds because incentives are there.

I don't understand how 50/50 split increases selling pressure, currently it is 75% author rewards (50% liquid, 50% staked) + 25% curation rewards 100% staked.

After HF 21 it will be 50% author rewards (50% liquid, 50% staked) + 50% curation rewards 100% staked.

So you can see from the bold sections above that staking will increase. On PALNET I think sell pressure is because they have miners, whose only incentive is to sell and not provide value, also their total supply cap and circulating supply is high, if you look at the current circulating supply there is 15 Million tokens, and the total capped supply is 7 Billion, their market cap is 530K, bitcoin have a marcap of bitcoin is 188 Billion and have a similar circulating supply of 18 million (PALNET 15 million), so the issue with PALNET is not the reward split but rather then tokenomics keeping the price low.

Hope this helps and happy HF 21 to you!