Here's how we've redefined the houses:
Gryffindor: summarized in the books as those who are brave, though that's not a very helpful definition. We've settled on a definition of those who are concerned first and foremost with justice and principles, even at the cost of some discord. Gryffindors want to make a point of things, and might have a hard time compromising or communicating. Examples: Liz Warren, AOC, Bill Russell. You might map the Enneagram personality types 1 (the Reformer) and 8 (the Challenger) to Gryffindor.
Ravenclaw: summarized in the books as those who are clever. We've decided this doesn't only mean those who like to study schoolbooks! In our telling, it means people who relish the world of the mind: they use intellect and reasoning as their first line of encounter with the world, and they seek wisdom, experience and exposure to new things. They're more concerned, ultimately, with understanding new ideas and parsing arguments than with who is ultimately helped or hurt. Ravenclaws could have a hard time in situations where their theories aren't working. Examples: Barack Obama, Anthony Bourdain, Matt Yglesias, Gregg Popovich. You might map the Enneagram personality types 5 (the Investigator) and 7 (the Enthusiast) to Ravenclaw.
Hufflepuff: kind of never defined in the books; I think there's one line that calls them "loyal". We've decided this means people who are first and foremost helpers, whose instinct is to help before they might, say, try to articulate a view of the systemic roots of a problem, or put themselves out there to change it. Might have a hard time when their good intentions aren't appreciated. Examples: doctors, Ellen DeGeneres, Bill Bradley, Pete Carroll. You might map the Enneagram personality types 2 (the Helper) and 9 (the Mediator) to Hufflepuff.
Slytherin: in the books they're basically the evil ones, but if you try to articulate their identity positively, I think you get something like Ayn Randism: power as something of the natural right of each person, and the focus of life as a struggle of various powers for their due, and space to be heard. Might agree that the ends justify the means. Examples: Fidel Castro, Ayn Rand, Michael Jordan, Kobe Bryant. You might map the Enneagram personality types 3 (the Achiever), 4 (the Individualist) and 6 (the Loyalist) to Slytherin.
An interesting wrinkle is that people can change over time, or have layers -- e.g., pre-Hajj Malcolm X was a Ravenclaw whose public face was a Gryffindor, but El-Hajj Malik El Shabazz became a Hufflepuff. Oprah's brand is Hufflepuff, but behind the scenes she's super Slytherin. Running against Obama, Hillary Clinton positioned herself as a Slytherin, but by all accounts she's a total Ravenclaw.