I agree, Xonotic is a great game and a lot of fun. Also it is highly competitive. It is also a blast at most lan parties where it's been played.

Only thing Xonotic really lacks are active players - typical chicken and egg problem. Although it already got better. And servers are online en masse. Maybe Xonotic's lack of active players is a result of somewhat overcomplicated accessibility for less computer savy gamers, as the set-up (ingame) and the heaps of options are a little bit too much and confusing.

Actually, I think it would be nice if the game starts into a "beginner" mode, which promts for basic things intuitively. The game does it already for Playername and such but important settings such as Field of View are hard to find. Well, it's open source so maybe I should be looking into that :)