Yes, it's ok with me to ignore the price entirely.
Cribbing from the dragon:
Frightful Presence (Ex): The General can unsettle foes with its mere presence. The ability takes effect automatically whenever the General attacks. Creatures within a radius of 10 feetare subject to the effect if they have fewer HD than the General. A potentially affected creature that succeeds on a DC X Will save remains immune to the General's frightful presence for 24 hours. On a failure, creatures with 4 or less HD become panicked for 4d6 rounds and those with 5 or more HD become shaken for 4d6 rounds. The save DC is Charisma-based.
Red text is because I'm not sure a 1 HD or less limit is going to be very interesting for his likely CR. So the question is whether we keep or change that text.
If I remember
Oriental Adventures correctly, the original power could be activated at will without any effort - presumably the high level samurai just assumes a threatening attitude and he's such a terrifying badass that minor opponents will be scared off.
That suggests it ought to be a free action rather than something that requires the General to attack.
The original power is relatively weak, affecting only 1 HD creatures and all, so I'd rather not have it as powerful as full "dragon fear", although I agree that if it
only affects 1 HD creatures it's of scant use to the General.
Hmm, how about if we make it 1 HD = panicked, up to 4 HD = frightened, 5 or more HD = shaken.
I guess we could also reduce the duration. Frightful Presence's 4d6 rounds is rather long. The "demoralize opponent" effect of the Intimidate skill only makes the target shaken for 1 round.
Actually, that gives me an idea. We could make this a "super intimidation" ability that uses the same mechanism as demoralize opponent (An Intimidation check vs a level check (plus Wisdom and fear modifiers), just to be different.
Although a Will save works just as well for me.