What really needs to happen is have a centralized service like coinbase launch that allows people to store their darkcoins on it for a percentage of a MN. Lets call this website "MasternodeShares
People with say 100 dark would get 10% of the masternode income during a month before fees of the website.
The huge hurdle of this is the actual implementation of setting up a full masternode; that is, having a unique static ip address for each one.
If the codebase was changed to allow multiple MN's to run on a single IP, that would solve this issue. For instance have masternode genkey also have an address flag.
masternode genkey X5490fja0fasdfsadfad
This would allow a website to launch while only utilizing one IP to run their service. Also, if this change was made, it would bring down the cost of operating multiple MN's substantially allowing a wallet of 5000 to run from one IP.
As far as increasing the percentage that goes to MN's: honestly, I'm actually against it. Mining at the moment is extremely unrewarding. Instead of taking income away, changes should be made to make it easier to operate MN's. Like above, a website that pays people in MN shares and easier operation and set up of MN's themselves.