Snowboard size advice

Hi guys,

I’m considering buying the Capita Outerspace Living or the YES typo as do it all snowboard. I mostly ride groomers and pow and always try to go for side hits and natural features. I’m also planning on learning more park stuff but I have no clue what size board I should aim for.
I’m 184cm tall and weigh around 68kgs. I’m unsure whether a 156 or 158cm board would suit me better.