Masteries or complete game content for better roster - brand new account
Looking for advice for a brand new account (F2P 1 week old). In the short term is it better to use units for full energy refills to complete game content such as Acts 3 completion/exploration in addition to Normal/Heroic MEQ to build a stronger roster of 3/4*'s or to save them to unlock Pearce, Precision & Cruelty which would cost 1,620 units?
Right now I only have 2x3*'s and the rest are 1/2*'s, I'm sitting on almost 800 units, Act 2 is complete but not explored and parry/limber/dex/stupefy are all unlocked.
Short term goal: participate in upcoming wars and AQ maps 2/3 to earn better rewards while completing story mode & MEQ to strengthen my weak roster.