Your 154 isn't so bad all-in-all, just on the small side of your range. Mostly it's about your riding style and preference, along with boot size (but your 9.5s will fit it all). I feel that if youre wanting something all mountain, keeping you all over the place when it snows and in the park when it's all tracked out, you're a good fit for sizing up! I would demo something just to feel the difference, but 5cm is only an inch. Only half an inch tip and tail ( if that eases the pain) heh. I think that if you get powder you will find even a 159 way more comfortable. This extra length will make those hard turns stick and get even more powered out. But I am in the opposite position. I have a hard time thinking I can downsize.
I'd start staring at the Jam, Riot. Goliath can be in the corner glowing if you want something more 'playful'