It would be ideal for these situations that the server is lagging but lets not run this down too fast because:
- how often does it happen that a server needs to be manually restarted?
- will this give the moderators power they actual need or is this solvable in another way
I would say let the server autorestart when there aren't any players on instead of giving moderators something I see as a very big power and responsibility
Or
Give someone that has been a trusted and reliable staff member for a while to be able to judge the situation and perform the restart command
But that is just my opinion