I think the project is neat. It certainly is an opinionated way of doing a layout and it reads quite nicely. If CSS classes were provided as an alternative I think the project might have more adopters.
Good work :)
I agree with you, I think this is clean and easy to use.
Personally, I've stuck with Bootstrap for quite awhile now. It's not perfect but it's pretty good, well documented, and I work to keep it simple. So I don't really use a lot of what Bootstrap does and that's why this project appeals to me.