Froxlor is a wonderful alternative to all commercial and free competing products I had to use over the years. It is secure, stable, well performing, and does not get into your way administering your server, while doing the boring stuff for you.
Modern PHP based architecture makes it easy to adapt it to your needs, and will ensure further development.
The project team is very active, responsive and open to suggestions, as well of course to contributions. Whatever you have used before, give it a try!