Port Scan protection, PortSentry / PSAD
Plesk has fail2ban but seems to have no port scan protection, Something like PSAD or Portsentry would be good to be included to allow blocking and reporting on portscans making plesk more secure for everyone.
Port scan are not really threat they just fill up your logs really. you can always change your port 22 aka for ssh to another number.
I recently setup a new server with plesk only to find that some machines fro 79.247.96.x scan it for open ports every other second.
There have been 40000 probes in the last 24 hours.
So I strongly favor a plesk addon against port scanning