Thanks for sharing the link, it's a really interesting read.
I'm curious - wouldn't a large, variable geometry lifting body do the trick? Land like a shuttle would, but with a bigger wing, and deploy more wing and lift devices as you get lower.
The wingspan required for something like a manned spacecraft would put the Spruce Goose to shame. You need something huge to be able to slow you to a reasonable speed.
You can bet that there's no better simple solution. This problem has been analyzed extensively by groups with lots of resources (intellectual and monetary).
Besides the other commenter who mentioned the size of the lift surface, think of the mass requirements, the variable atmosphere density mentioned in the linked article, the need for an autonomous lander (because of light time), and the small amount of time you have to land.
I'm curious - wouldn't a large, variable geometry lifting body do the trick? Land like a shuttle would, but with a bigger wing, and deploy more wing and lift devices as you get lower.