I meant the feat to completely eliminate the chance of a returning trip not provide a bonus to the role. No more role would be needed. Would that be too powerful?
The Improved Disarm feat does exactly that (+negating the AoO) at the disarm maneuver.
I wouldn't make Improved trip a Prerequisite to this feat. They both improved a characters trip skill but in different ways. Plus I really don't think that it has the power of a third tier feat.
It is a great feat that I suggested the need for this feat before.
Hmm... the only problem I can see is that someone with this feat and improved trip can make trip attempts all day and never face any consequences (other than the waste of an attack when a trip fails).
Now, if he fails (and that's the only point when this feat comes in) he'll get attacked by the enemy who in turn wasn't hurt at all.
And you should mind that tripping is most effective against humanoids. Very few monsters can be tripped with a reasonable chance of success.
The draw back is that if fail the trip you also miss a chance to hit the opponent. Having run the numbers it is only a better attack method if you have the advantage in the trip contest. Against large creatures or those with 4 legs or both you are not usually gaining a big advantage. Even at a 70% success chance with the trips the gain is usually right around 10% more hits per round.