Get Everything Done

I'd imagine theres a niche for being able to curate ideas, tools, etc and design a workflow system, customized for an individual's needs. Have any of you seen anything like this?

The key would be to identify critical variables that would inform the methods and tools. And then once the psychology bit has been taken care of, it's a matter of borrowing ideas from Forster, Allen, etc., etc., and creating something that appeals to the emotional touchstones of each individual.

Clearly this is something I have tried to do in my own life - though I imagine I'm too close to my own work and style to be effective.

What critical factors would need to be considered if one were to customize a system for somebody else?