I've hunted while wearing my great kilt, the plaid really breaks up an outline nicely! Plus there is a very special freedom of movement while wearing it!
Just like choosing modern clothes to wear, you gotta ask if it is comfortable, warm enough, quiet enough, and breaks up your outline. Other than that, it's all cosmetics. But I would still carry a nice Viking hand axe with that get-up just to keep wheelie bow guys from snickering. I think it adds a degree of authenticity and shows you are serious.