Solution is acting as a gateway for remote administration tasks. Available on HTTPS only. Allow RDP, VNC and SSH from it to our applicative end servers. Access is restrained to Admin with 2FA.
Pros
All port closed except 443
Attackable scope is limited
Administration tasks are under one entry point
Need
Privileged users accesses should only be made through a secure portal no matter is the end-devices.
The client wants to rely on this service so emails can go through and alert teams on time. The service must be available or alert people in case of failure.