I would say to take out the gearhulks and the ballista, drop
Hadana's climb down to 2 and then add 3 copies of each. This will drastically lower your mana curve and you'll be able to play more creatures in a turn helping you
explore more. Remember, the theme of the deck is
EXPLORE, +1/+1 counters will help you win your battles but you have to consistently
explore in order for the deck to run as you intend it to.