Doesn’t have the Hl2 sprint meter i noticed. Major flaw design or purposely left out?
It’s annoying to have it for a sandbox game 
Purposely cause why would you need to stop sprinting in a sandbox game (well if your runninng from/to a minge/contraption)
No, but if you want it here ya go.
http://www.facepunch.com/showthread.php?t=904847&highlight=sprint
Left out, but not always on to add a bit of speed. I did this on a DM build server for the same reasons.