Ok here are my opinions on that:
I think the logical categories would be as follows
Melee (knife, kerrblades, fists...)
[throwing] (for grenades) (wich category are they in anyway right now? explosives?)
Pistols (one handed/ "secondary" weapons)
Rifles (assault, shotgun, sniper, MG)
Artillery/Explosives (rocket launcher, grenade launcher...)
While it is totally different to fight someone physically with your fists or a knife compared to a pistol duel it is quite similar to shoot with a shotgun or an assault rifle.
Snipers could be in the rifle category as well because modern assault rifles are mostly available in assault as well as in sniper implementations and there is no real difference at long ranges. If you are bad at 300m with an assault rifle you are definitely worse with a sniper at 700m. If you can handle an assault rifle at longer ranges quiet well you have everything you need (ballistic theory) to handle a sniper. Then only range is the problem.
I know that focuses much of the weaponry into the rifle category but I think that is more closely to reality. Maybe a submachinegun/shotgun/"close quarters battle" category would be a good idea as well.
The current category distinction is simply unlogical to me.
What are your thoughts about this?