This is absolutely necessary...
Weapon mechanics in this game are currently iffy at best, and all but impossible to actually get a feel for in match. Recoil patterns, pull direction, damage per shot, basically none of this can be figured out in match, especially when inconsistencies of bugs come into play (I just got one hit killed from like 60m away by an MK18, through an ION helm, full shield, and full HP).
There is no time, at all, to test, adjust, and retest sensitivity in game, let alone enough to actually get it to where you need it to be in relation to what you use in other games... You basically are forced to use a premium service (mouse-sensitivity.com) to do it for you and then apply it in the ini file. This is bad, we need to be given the means to do this ourselves.
We need a dedicated solo area to test things and get properly acquainted with the weapon mechanics.