Would a new tsar, a regent, and no Lenin save the monarchy?

Could assassinating Nicholas II, installing his son with a competent regent, and keeping Lenin out of Russia prevent the revolution?

It requires too many additional assumptions: a competent regent, a more popular monarchy, and Germany abandoning a useful plan to destabilize Russia.

An audience proposal removes Nicholas II, installs his son under a capable regent, and prevents Germany from returning Lenin to Russia. The scenario first has to produce a genuinely competent regent, which is a large assumption within the existing court system. Killing the tsar would not automatically make the monarchy popular or eliminate the grievances feeding revolt. Germany also had a direct strategic motive to send Lenin, so preventing that step requires another deliberate change. Compared with these linked political assumptions, a better-run Dardanelles operation stays closer to decisions that were historically available.