Tony, I've spent over 20 years landing on elevated pads offshore, and have done close to 20,000 - 9000 in about 6 months once. The wind is generally a good thing, until it starts having the flow interruped and redirected. If you do install a pad, try to have a breezeway under it, so the wind can blow underneath, and not be entirely redirected upward, which results in it blowing almost directly downwards on the downwind side, which can make for interesting approaches, and very interesting shutdowns and startups. The main rotors can strike the tailboom easily under those conditions. The worst thing you can have is a completely vertical wall right up to the pad - a breezeway underneath, 20' or higher, makes a world of difference.