Since PoB mining is quite straightforward. By creating value, you can get a chance to earn tokens. Curators, creators, and investors are creating value by doing their jobs. Most of us are playing different roles doesn't matter how big or small. Even I think a 50/50 split is fair to everyone. The same creators who are earning these tokens have an incentive to stake them and start curating as well. There is no other reason for people to stake their tokens. If we go ahead with a 75/25 split then it will invite self voting since curation will not be profitable anymore. People will choose to go greedy that way. Also, people will put their favorite authors on auto upvote in order to get maximum rewards from curation. So ultimately it will defeat the purpose.

Also, curation trails are quite important. We cannot expect everyone to curate manually every single day. Even if someone manages to do that, they cannot be online 24/7. Hence implementing several curation groups would solve this problem. Everyone can delegate to them and earn returns as well.