You can get better by just playing certain maps, like on my map cycle i only have Mirage and Inferno. The more you play them, the more you know the callouts and the places people frequently go. Good map knowledge puts you 1 step ahead!
Upgrading my pc with a new processor and graphics card, my pc atm runs Arma poorly so gonna get i5-3570k(matches my socket) and GeForce GTX 960? Will it majorly improve gameplay and such?