Mini account help.

MyersVoorhes

I have a mini account that I'm trying to build, and I'm wondering what I should do to start boosting up the profile. I know that arena is a big help but I can't take anybody up to keep a win streak. So I'm wondering what content I should be working on. I always debate on whether to do story mode, the daily catalyst quest or monthly event quest and I have full energy refill in the stash expiring. Any input is welcome, thank you