Since Twig autoescape is on, there are double escape bugs. If you can fix them by refactoring code into Twig templates, that's great. If not then wait for an easy way to create HTML on the fly without having to create a theme function / template. It's already RTBC, it's a matter of days to find its way in. Regarding SafeMarkup::set calls, there is an issue to refactor and remove the ones we needed to add to get tests pass and so adding more is not acceptable (the reason for writing this announcement are the quick fix issues I need to whack trying to fix double escape by adding more of these).