Majority of those who kick against the proposal have argued that the model will give more power to the whales and take away reward from the curators who add value to this blockchain.

Another argument that has been put forward is that a 50/50 curation model may end up demoralizing curators, quenching their interest in Steem and moving their blogging activities to other rival blockchains.

Do you mean authors?

With this remark I get my share of future 50% :(

One important point we often ignore here is that neither Steem, Steemit nor any other dapp on here can exist without dedicated investors, investors who have a long term perspective. And who are such kind of investors? They are those who hold Steem power.

Therefore, as a way of providing incentives to SP holders, a 50/50 curation model is necessary. If investors can earn more from holding Steem, it is likely that more investors will come into the scene. And that could do some magic to the price of Steem in the long run.

My take is that these investors have enough reward already. They don't need even bigger percentage. In other words, they don't need to take even more away from other contributors.