I have found many topic with the same question but I have never seen that it was accepted as a wish and instead saw only workarounds I already know.
The wish is to have the ability to decide, if the panels following curved reference line are plane or curved. The way I see it is to have option in settings to decide which one will be used. Then of course it could be possible to change in polygonal curtain wall in each segment if needed. The same goes for creating curved frames. From experience with reconstructions many times there is need to fill arc with new glass wall which has the frame around the arc. I know that there is workaround to have the scheme divided to small pieces and and then to delete unwanted frames/mulions but that is slow and when there is change, we need to pick multiple parts of curtain wall. So again, new option in setting where we can decide if the boundary frame is going to be curved or plain.