The Qing Dynasty is doomed to fall because It is a Non-Han Race/Empire and the Majority Han just want to get rid of it no matter what. The Hans couldn't accept a Manchus as their constitutional monarch in whatever terms.
though I alway thought that what if the last Qing Dynasty was a Han/ Yellow Emperor Empire...If the Empire is not as rotten to the point of despair or if the Dynasty promised to give back the adminstrative powers to the people in return for constitutional monarchy. Maybe the Revolutionary Powers of before 1911 will accept a settlement of constitutional monarchy as afterall the Monarchy is still Han and their own.
Didn't Yuan Shi Kai, the Northern warlord, manage to have himself proclaimed Emperor?
If so did he take the "mandate of heaven" and should any restored monarchy be his descendents?
Apologies if I've remembered incorrectly