Flakmage isn't the only offender.
Secret Crystal Runner is sometimes played onto the board where the opponent can easily trade their 5/1 (or mage 4/1) for free next turn.
Occult Conjurer isn't always a good play option if it's not getting the secret bonus, and you're almost out of cards.
E.g. Bot plays conjurer (4/4) without a secret on deck, plays Torch into 5/5 Crystal Runner. Next turn I have an empty hand and the opponent trades the now 5/1 Crystal Runner into my Conjurer for near-nothing.
Bot uses Cloud Prince a) without a secret on deck b) into an inefficient target (like a 1/1 token)
The bot plays poorly around Hunter Secrets.
E.g. Hunter plays a secret, I have a Flakmage on board (3/2). Bot plays second Flakmage without checking for Explosive trap, now both Flakmages are dead.
Don't get me wrong, it's still a very good deck/bot. with some tweaks it could easily hit Legend. Learning to save Counterspell for massive swing turns e.g. Paladin's turn 9 Libram of Hope is a big issue.