These are what I think are the best weapons in each category
http://fallout.wikia.com/wiki/Fisto!
http://fallout.wikia.com/wiki/Shishkebab
http://fallout.wikia.com/wiki/Callahan%27s_Magnum
http://fallout.wikia.com/wiki/Double-Barrel_Shotgun
http://fallout.wikia.com/wiki/Sydney%27s_10mm_%22Ultra%22_SMG
http://fallout.wikia.com/wiki/Xuanlong_Assault_Rifle
http://fallout.wikia.com/wiki/Experimental_MIRV
http://fallout.wikia.com/wiki/Firelance
http://fallout.wikia.com/wiki/Scoped_Gauss_Rifle
http://fallout.wikia.com/wiki/Tesla_Cannon
http://fallout.wikia.com/wiki/Nuka_Grenade
http://fallout.wikia.com/wiki/Grenade_Launcher#Broken_Steel