If not, there was the previous solution by Alex and myself. But it had the problem of not being extensible to user types. Maybe that's worth a second round of thinking? I don't remember exactly what prevented making macros allowing the user to extend it to custom types.
What prevented adapting the old system into an easier to use library that users could easily use to give their own types alignment safety in std::vector? It's been a while since I worked on that code so I can only vaguely remember how I got it to work :( (Yes this does count as me volunteering to try and make it nice and easy for people to use if that's an acceptable solution.)