The thing about boosting damage is that fighters already have plenty already and that isn't really helping. The level 3-9 abilities will each make him pretty ridiculous there yet without fixing anything. That said, I like the first ability that gives them the boring damage boosters for free. That frees up feats for more interesting build choices. If you wanted to take this a step further you could give away the whole fighter tree and perhaps the ranger combat style feats away for free as well. That'd be a power boost to be sure but nothing nearly as bad as what you're proposing and it'd encourage a wider variety of interesting feats rather than having a 1 trick pony.