Last season i tried some 171s and they were great for me but I did more aggressive fast skiing and off piste. that said for jumps shorters better, but I think that 171s would be perfect for you.
I also tried some 156s which when they got to a decent speed just ejected me
In the end its up to you whether you want a more stable ski that is faster with a longer turn or a quicker playful one that is less stable at speed, but I dont think that the difference will be huge, and youd be able to do what you want to do with either anyway.