Why not to raise com_maxfps from 125 to 250?
aspects of setting cvars "rate" and "cl_maxpackets" already changed at last ql updates.
There are modern LCD monitors that can output more than 120hz and limited to show only 125fps.
QL physics are fps independent.

More fps = less delay from videocard to monitor even at 60hz displays.
What are fps limits of others FPS?

quakeworld = no limit
quake3 cpma = no limit
quake3 defrag = 140fps limit
tf2 = no limit (not sure)
warsow = no limit
xonotoc = no limit (not sure)
cs1.6 = 100fps limit
csgo = no limit (not sure)

Vote at QL Forum suggestion thread: http://www.quakelive.com/forum/showthread.php?34236