Thanks Snowolf for the input, if I understood you correctly I should get 160 for freestyle/ park ? If I go with 159 (because that's one of the options that I can buy) how much difference that 1cm can be?
Also, you say "board length is determined by the rider's weight primarily", how can I choose a board based on weight when there is no weight data for most manufacturers?
How can I know if particular board will hold my weight?
Most manufacturers do publish a suggested weight range for their boards.
Pretty much any board is going to be capable of holding your weight. 200 pounds is big but it's not that
big. For reference I'm 6' and 210 lbs and no problem riding anything as small as 155. I ride 156/157 in the park and 161-163 all mountain.
1cm is not going to be a huge difference but 5cm (downsizing from your 164) will probably be noticeable at first so excpect a few days maybe to get acclimated to riding a shorter board. I would say you'll be fine on a 159 for most boards especially if you want to use it in the park.