Line blend 171 or 178

I'm looking at getting the line blends as a first time buyer i'm not sure whether to get the 171's or the 178's.

I'm 175cm and about 64kg. I'm an advanced skier, tending to hit groomers with speed, play about with any jumps, look for off piste powder when i can and hit park occasionally and i will be looking to improve my skiing substantially with these especially doing a season next year. Looking for an all round playful ski which can go anywhere and i've heard these are the skis for that but I'm stuck on which size to get.

How much does the early rise reduce effective edge should i compensate by getting the 178's or am i too light for the 178's?

Thanks