I'm not so sure. Given the current goings-on on Steemit, I think the most likely scenario will be that:
- blind voting-for-profit will go up, and stay well within the existing voting patterns, some of which are circle jerks;
- voting-because-one-likes-content will go down;
- average Steemians rewards from voting will move from negligable to twice negligable;
- their rewards for posting content will go down.
I don't think increasing the curator's cut will increase proper curating, it will just increase the rewards for those who vote for rewards only rather than for rewarding content they like.
I suspect all it would do is make the in-crowds and short-term ROI-seekers work slightly differently, while at the same time increasing the income of those who vote for profit and decreasing the rewards for content creators.
The long-term/short-term outlook of those with the big wallets is key here, not the percentages.
There's only one way to find out what would happen, so we could just try it, as long as it can be reversed when it doesn't work as intended. Nothing wrong with experimenting as long as you say beforehand what you will do with the outcome of the experiment.