Quit playing in S2 then.
Thank you all for your replies.
I believe I have enough information to move forward on it.
To the OP, the max progression rewards are generally reserved for the stronger rosters. Without boosted champed 4*s, you will not be able to hit 1.2k.
My advice for what it’s worth:
Roster and champ most/all 3s then build your 4 army.
Don’t level your 5s until you have plenty of champed 4s
Don’t level non-top tier 4s until all the good ones are champed. Hoard ISO if you need to. Elektra/Baglady/Fury etc will NOT help you to get good scores, Rhulk/Bobby/Cyke etc will.
Good luck!