Oh and by the way, I believe I forgot to mention before:
This is still quite awesome on the whole, despite my balance gripe regarding large size.

On a spiked chain tripping/AoO build against an army, sure, anyone would want to be Large. On a charge build, you probably reach the person anyway. Against smaller numbers of foes, you don't need to threaten in a huge radius. I'm not so sure it's as great as you're saying. It's just distance, not killing power. And if it is good, let people have it (fighters can't have nice things etc.). I will consider moving Large size up to Moderate, but it's really hard to judge.
Even on a charge build. Let's pretend your charge doesn't kill them (cause if it kills them, who cares?) Wouldn't it be nice if they couldn't attack you without you getting another attack? Oh wait, you can do that. Good old large size+Lance.

Fighters can have nice things. But this is still a moderate ability, I'm pretty sure. Small size is less good because you don't get reach. But that's another issue entirley.

Unrelated Matter:
# 10 feet faster base land speed. Small creatures with the dwarf unique racial power instead gain 5 feet faster base land speed.
10 ft speed increase seems a little weak for a major power. When compared to stuff like Tremorsense, delayed Fly progression and +4 to spot and listen say, this seems underwhelming. Though perhaps not underwhelming enough to be moderate.