What people are saying in a roundabout way is --
YES. It's too much.
That guy gets 4 AOO's a round, plus has improved trip and etc.
Before being enlarged, it's "broken" in straight melee (he owns any other non-tripping non-reach opponent). After enlargement, bye bye.
By far the most overwhelming 2nd level build out there.
So yeah, you definately DO have to make different/strange encounters (a standard encounter will be a cakewalk). That's why people are saying use reach, missile weapons, cover, etc.
By the way, this is a good tipoff that a given character is overpowered, i.e. the GM is forced to change that way the game is played, every battle. "Out of the book" combats are a joke, etc. It's legal, it's just disgusting. Particularly for 2nd level.
This particular tricked out 2nd level fighter, even before enlargement, can be expected to handle 3-4 sword-n-board 2nd level fighters. By himself. At the same time. After enlargement, with a reach of 20, plus more strength etc. Gross. I've seen these guys in action; really makes non-reach fighters look stupid.