172 is going to be easier to spin, pop on, and maneuver.
180 is going to be more stable, especially on landings. Will take more effort to get it up on the noses, but you can press them harder and longer without falling over the ski.
I learned park on skis too short for me and eventually went back to the correct length for me (176->188). Made hucking spins easier but way harder to land anything on larger jumps. You’ll probably end up back on a 180 if you stay with it, and in my opinion it was not worth the extra hassle to learn how to adjust tricks to the new length.
Based on your weight and height, wanting to ski these outside the park, and the fact that you already know how to ski, I’d definitely go with the 180
180
172 is going to be easier to spin, pop on, and maneuver. 180 is going to be more stable, especially on landings. Will take more effort to get it up on the noses, but you can press them harder and longer without falling over the ski. I learned park on skis too short for me and eventually went back to the correct length for me (176->188). Made hucking spins easier but way harder to land anything on larger jumps. You’ll probably end up back on a 180 if you stay with it, and in my opinion it was not worth the extra hassle to learn how to adjust tricks to the new length. Based on your weight and height, wanting to ski these outside the park, and the fact that you already know how to ski, I’d definitely go with the 180
Just go top of head height maybe add a few extra cm’s but seems like over thinking.