Ever wonder what to upgrade,well this will answer that question.If you are 1-2 'STAR' just focus on getting mech and having fun you don't really need to upgrade mech and weapon in the early game but still upgrade your mech but try not to spend alot of Credits and A-coins (Dont Buy:MD and Puma)If you are 3-4'STAR' you have just enter the mid game,The best options is to buy Stalker,Tengu and Aegis for the weapon there is alot  options but the one you need to buy is the stormrack,revoker,helix rack,cryo launcher and the ember gun these Five will carry you until you reach the late game(Don't Buy:Arachnos)