That said, TeX got a lot of things right."
So why not resist the start-from-scratch instinct and build a framework on top of TeX instead? In that way, you would not only inherit all that TeX gets right already; but most importantly, you gain an existing huge userbase practically by proxy by making it easy for many TeX-using authors to use your framework without having to change their existing workflows or rework their source files (including, as it happens, many in this very thread, as you can see).
I understand starting a new publishing framework from scratch is much more appealing than the daunting prospect of building a higher-level lispy macro language on top of TeX that achieves your goals of readability, power and ease of use; but there are reasons why sometimes improving existing frameworks is often preferable than tossing everything away and starting over from scratch[1].