I think it would be a good idea since you have a park board already, and this would be for going bigger
I'm usually 190-200 but I'm pretty leaned out and strong for my job, so a 63 is nothing to me... If you're in shape, a 62 will be just fine. You'll adjust and then the short stick will be that much more playful
"When I do good, I feel good; when I do bad, I feel bad. Thatís my religion." - Abraham Lincoln
i am currently riding a burton se7en 09 157for a park. I am 5' 10" and weigh 185. Would I be able to ride a heritage in a 160 for all mountain?
I'm similar (6' and 175lbs) and ride the Heritage 160 with absolutely no problems, it's my all mountain resort ripper as it handles the freestyle/terrain park as well as the powder, trees, and groomers.
If you want one board, this is a great size imo but like Milo mentioned, if you already have a park board something bigger is an option. I also have a regular cambered 162, and my splitboard is 166, and the rideability of the larger boards isn't that noticeable.