Note on installing the Ninja Pro Firewall into UNA.  The suggested use of the .htaccess file, and the php.ini file did not work for me, however, when I used the recommended Apache with CGI-FCGI and the suggested .user.ini file, then the firewall installed into UNA.

It has a control panel that is made usable with the premium Ninja Pro+ Firewall, and it allows you to block entire countries from the control panel.  I can do this on my host, but it would provide a backup firewall inside UNA if used.

With the Pro version (not Pro+) you have the Sensi firewall which alone is a good feature to have.