Figure out the ideal learning journey for Magento devs.

Then bake that into an interactive Codecademy-style experience that bootstraps a dev environment for them to work against.

They can hit the ground running without having to fight dev environment setup battles.

(Are they really Magento devs though without getting to the brink of despairing of life itself over dev environment setup issues? I digress...)

Have tie-ins to Magento cloud as well.

For bonus points, tie in a mentorship/community component where they can go for questions and support.