Funnily enough chaosesque was started because xonotic proper wasn't realistic
enough in damage.
Chaosesque has many of the features. Bullets are fully ballistic, there is
bullet drop and dispersion(spread etc). There is headshot and coreshot (heart
etc) detection. Weapons do realistic damage. Also there is shooting through
walls, which depends on thickness of the wall and it's material (which if not
set by cvar is detected by texturename regex's, so even unknown maps will
usually have correctly detected materal properties). Ofcourse it also has
futuristic and medeval weapons too, but those can be switched out via the
g_weaponreplace_bla "somethingelse somethingelse randomsecondthing" cvars.
Divverent made the ballistic bullet code. It was simply extended to more
material types.
The speed of the player is also controlled through cvar so it can be brought
down to a different level. Everything in the game, almost, can be changed by
the server admin (or player 1 if you're starting it from ingame) via cvars.
An easy way to search your options is to go to the misc menu and then
advanced settings and search by wildcard:
*speed*
You can also start out each team with different weapons etc.
Also in the Xon/data/maps/ directory in the iso is sc_tiles.zip
That has 50 or so realistic buildings with interiors, plus more tiles for
roads, railroad, airport etc. If you unzip that into the /maps directory
(preferably in your ./xonotic/data/maps folder) you can quickly make a little
town by importing the tiles. Takes 5 min to make a realistic map. (Keep
texture lock on in netradiant, set the grid to the highest setting). Then
compile. If you want to know how to make a quake3 map, bubbas quake3 map
tutorial is