feels like its just strictly worse than Toothy Chest most of the time.
I don't see it that way at all. You can kill toothy chest for free as long as you have a total of 4 attack or more among your minions. You can only kill this for free if you have a single minion with 4 or more attack. Not to mention this costs a full mana less.
My first thought was play this on 2, next turn Inner Rage it into Rampage. And since you have a mana left you could play Abusive Sergeant on it as well! Turn 3, you've got an 11/6 that can attack face, and will be 9/6 after your turn.
Or instead of Sergeant you use Acherus Veteran for a permanent +1 attack making it a turn 3 10/6 minion that is ready to attack.
Or if you have just Marksman, Inner Rage, and Rampage in hand going second you Coin -> Marksmen. Second turn Inner Rage -> Rampage for a 9/6 minion on turn 2!!! Good or not, I'm going to trying to find ways to make this guy work in various decks early on.
I don´t think it is as bad as most of the people say it is ... yeah sure most of the time it could work in Warrior with stuff like Inner Rage for example - but it could also work in Priest with Inner Fire or even Topsy Turvy. And it´s only 2 Mana so you can play it early