There is a fundamental difference here that can't be ignored.  In that pie chart from SPR that you show the different percentages represent large mining farms or individuals that can take advantage of the absence of pools and monopolize the network from a rewards perspective, these people are getting all the coins, some mining with optimized miners.

In the pie chart from DRK those larger percentages represent a lot of different individuals. Pools were created for a reason it facilitates a larger group of people to come together and mine and compete with large individual miners. By keeping pools away you are only making it easier for large farms to abuse the system, it creates new weaknesses.

A better solution would be to create a better P2Pool system that allows both pools and a better decentralization, which is a novel goal but not quite accomplished by the no pools  approach. In my opinion it is just something to sell people on but not a strong differentiator, even a weakness from other aspects.