Reply:

Your problem, largely, is that you are in the wrong menu.

You have chosen to play the pre-programmed "single player" "campaigns"
(of which there are a few, but it seems you have chosen the first: xonotic
vanilla) (I suggest "Who Is The Greatest": a martial arts epic where you 
fight hand to hand up the list, instead). You will only get the game the
campaign-creator thought of there.... which does not include most of the
mod additions!

Go to Create>Multiplayer and create a bot match. There are 100 or so maps to choose from.
[IMG]http://endchan.xyz/.media/bb432b5ed035226d00c9f01124da29c2-imagejpeg.jpg[/IMG]

> Music sucks
Since you played the standard campaign rather than picking the maps yourself,
you only played the standard Xonotic maps in said campaign.

Go to Create>Multiplayer and say... pick... ArenaAutomatica... that has a soundtrack.

[IMG]http://endchan.xyz/.media/94f1f9287178cb809e81ed189733559f-imagejpeg.jpg[/IMG]

Fuse
[IMG]http://endchan.xyz/.media/cc15bc97e64d3d58781fde0245b30e61-imagejpeg.jpg[/IMG]

GardenRoulette
[IMG]http://endchan.xyz/.media/ec5af5e545b8e082d4e07425cf6183b1-imagejpeg.jpg[/IMG]

Implosion
[IMG]http://endchan.xyz/.media/430eef6449b5a4c0009db8133bdf73e8-imagejpeg.jpg[/IMG]

Silent Siege
[IMG]http://endchan.xyz/.media/dbcc8bbe0e70bfcdca827d524f373e87-imagejpeg.jpg[/IMG]

Final Rage is also suggested.
[IMG]http://endchan.xyz/.media/23f4b32b4bfe35c8a8445eca252220b7-imagejpeg.jpg[/IMG]

GrandChessboard, which is a large terrain map created to have lots of room for RTS style building matches (with the utilitool + hammer, crowbar) has good trax (It's on Disc 2 btw) 
[IMG]http://endchan.xyz/.media/58d448e9c19b41db32b2fb660c63784f-imagejpeg.jpg[/IMG]


The dearth of good music was an issue for Xonotic, so for the maps I have added, I've picked different opensource music.


Settings>Info gives a good rundown of various features and how to use them.

[IMG]http://endchan.xyz/.media/9d12bba703c87042b3c9ff36762e3881-imagejpeg.jpg[/IMG]

> Wep-on is lie!
The menu you want is Create>Multiplayer>Startweapons
[IMG]http://endchan.xyz/.media/9c477ef29b8a85f2fe077749e95f5cbe-imagejpeg.jpg[/IMG]

Also Create>Multiplayer>Mutators has options such as replacing standard maps weapons (with other sets, or traps, or spellbooks, etc)
and/or spawning other weapons in random areas:
[IMG]http://endchan.xyz/.media/353ab65d80881eec0d0f135a9a69d134-imagejpeg.jpg[/IMG]
(also foliage, monsters, turrets, water/oil/methane/slime/lava/chemical flood, city generation, baloons, bumpers, etc)

Other menus to be cognisant of:
Create>Multiplayer>MG
[IMG]http://endchan.xyz/.media/bd69442b9a8bf6cb5ef53ddd3014c6cd-imagejpeg.jpg[/IMG]
This is the mounted guns menu where you can set mounted guns to spawn.

Create>Multiplayer>Vehicles
[IMG]http://endchan.xyz/.media/3ec91d6fbfd377e4c727812b7977ce82-imagejpeg.jpg[/IMG]
Vehicles to start with

Create>Multiplayer>Spells
[IMG]http://endchan.xyz/.media/188294b7301be36e17fc701a3987fc23-imagejpeg.jpg[/IMG]
Spells to start with

And ofcourse the previously mentioned
Create>Multiplayer>StartWeapons

Where you can not only set start weapons and starting knowlege (amerios please
do not set this one: let's be realistic),but items to be spawned around,
and options for the multitool and utilitool (for building things: amerios are
forbidden from using these specific tool options unless accompanied by a latin friend)

With these you can set your gaming enviroment to be whatever you wish:
Modern, Futuristic, Medeval, City scape, lava wasteland, oil ocean, chemical plant, etc etc
All whilst zombie/solider/angel apocalypse occurs: You can do it.