It isn't always windy, unless you're hunting plains birds. However, my interpretation of "windy" may have changed since I moved west. On most days there is more wind than back home in IL. I'm assuming you're hunting the Hills. I've not hunted the Hills but would expect some wind. I've seen some strong winds in Rapid City while traveling through and WY is known for wind but more so in the open plains.
As far as Merriam's go, in general they are considered easy compared to Easterns. However, I think if you hunt public land pressured Merriam's enough you'll find that they can be as stubborn as an Eastern. I believe some of the "easy" title comes from Eastern hunters making one trip to hunt unpressured heavily populated ranches or reservations. For the most part Merriam's do not see as much hunting pressure as their Eastern cousins.
The toughest thing about Merriam's is they are constantly on the move, here one day and gone the next.
They do like to gobble. I believe most of them have looser lips than an Eastern. I call a lot to most Merriam's and don't normally have to be as subtle as a lot of Easterns require, but I have had to sweet talk a few of them in or go silent to entice a hung up bird in.
I don't know if it is their nomadic nature or the big country they live in, but they seem willing to come a long way to the call, and they can do it in a hurry. Their weak sounding gobble may convince you they are farther than they really are. The combination can result in bumped birds.
All of these generalities can be blown out of the water by that one bird just like those tough Easterns that have eluded you for days only to suddenly turn into a bird with a death wish.