PROS:
Beautiful setting and photos
Sense of calm when coming down the aisle
Amazing weather
Shoes are optional
More relaxed...you can customize ceremony how you want it without guests thinking you've lost it (lol)
Often less expensive than traditional weddings

CONS:
Sand in your eyes and hair if you get a breezy day
You may need to bring in your own rentals such as chairs, tables, tent for bad weather, chuppa if required or other wedding arch,
The bride's dress is guaranteed to be black at the bottom if it's a long dress
Female guests can't wear sexy heels if they wanted to