I know the pain of trying to choose usable keyboard shortcuts!! Urgh indeed.
I'm afraid (or maybe that's good) that Windows global shortcuts take preference so the start menu still opens. To be honest, I'd actually forgotten that ctrl-esc did that, I'm so used to keyboards with a Windows key.
Even shift- or alt- esc are not available. Not sure what alt-esc does but you loose focus on the current app. shift-esc is intercepted by Chrome to bring up its internal task manager. ctrl-shift-esc brings up the W10 task manager.
Personally, I'd be happy for it to remain as esc but I understand that this is not very beginner friendly. ctrl-q maybe?