Utopia founder here. Yep, I loved the idea of Frontpage, and learnt so much, and yet - it sucked so much in practice. What kept us honest here was having the real-time feedback loop between design and code, and real-time two way editing. It really pushed us to "only make the smallest, surgical updates possible", and ultimately "make sure the editor actually understands the code"

We also are trying our best to preserve intent (eg if you resize a flexbox element, we don't set a width on it but default to flexBase, unless there's already a flexGrow on it).