i'm about 180lb and would go w/ the 157 but i lean more towards the freeride side of things vs. freestyle. for you going w/ the 154 will allow you to flex the board more and be easier to initiate turns, jib, and seem more playful whereas the 157 will seem more solid while going fast. you'll be just fine w/ the 157 regarding turns etc. my vote for you would be the 157 for a good all mountain board.
and i cannot agree more on going w/ the TRS and rider's choice over the trice.