Okay I was told to 6 star wukong then bivald. Who's the 4th and 5th champ for the team? 

How many masteries should I have? /when should I heavy farm them. I think those 2 questions are the most helpful?

for masteries: usually don't farm those until 15. reason being that it's not very efficient for the scrolls you get. farming 15 ends up being about ~150 gems cheaper in energy value versus just buying masteries provided we're farming 15. usually we also spend our first 800 gems on kale/our campaign farmer which will help him be our dungeon DPS, and get us to brutal 12-3 for the most efficient campaign farmer. 

as for your next 60: I'd be tempted to bring War Maiden up. she'll be easier to book and has the all important 2 turn defense down on a 3 turn cooldown. i do think she's one of those champs you can stop at 50 with, due to wanting to replace her later and her stat requirements really only being speed and accuracy. 

affer that, criodan or armiger most likely. i think i'd go crio for now, armiger will likely be a bit squishy until your gear catches up a bit. in the meantime make sure you're grabbing copies of him from the market. 

Agreed, Armiger and Warmaiden seem best....

If you pull Dhukk, Uugo, Tayrel, Stag Knight, Deacon or any of the other epic AoE Dec Defense champs in the meantime, build that instead of Warmaiden.