I very much agree with @mmistakes, that most people come to these themes when they are fresh to the industry and just want to get rolling on GitHub Pages and move onto the next thing.
However I do like the idea of pushing alternative routes that may be more catered to open source theme gems, and may even be easier to setup. I’ve been working on my themes with the mindset that they could be used in a variety of ways - such as a gem, a fork, an installation on Siteleaf and so on.
I’d like to add Netlify, GitLab Pages, CloudCannon and a few others if I can. As long as it meant I don’t have to litter my theme / repo with special configuration files.