Fun, absolutely.
Practical, not so much.
Though an interesting fun idea, it complicates things adding time (to anything)
To have the time stored across server sessions (map changes/server restarts, etc), or across player sessions (join/leave/rejoin), you'd have to write the time to a file.
Storing admins and bans across those same sessions is often challenging and error prone enough - Personally, I do not see the benefit vs support requirement of adding the code.