156 only because u have bigger decks for other things, plus u want it for park right?
I weigh about the same as you and use a '54 proto for all mountain and '54 evo for park and screwing around on groomers and such.
Its not like you need it to hold up maching gates right?
'56 at 180lbs is not tiny either, its not like that is extreme downsizing. A 50-51 would be small.
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