The people, the political culture (the reddest of states), the climate (though it takes a bit to get used to the humidity) the cost of living, the cost of land, very green area (except in winter), the topographical diversity, decent hunting, great fishing, mushroom hunting, lots of naturally abundant medicinal and self reliant resources, good economy (after the oil bust of the 80's people became very fiscally conservative). A strong 2A presence, quite a few libertarians, low population density except in the two big cities (Tulsa & OKC), great homeschool climate, Wanamaker's gun show (in Tulsa), fairly patriot minded law enforcement generally, inexpensive fuel prices, lots of alternative energy options,
The bad would be the humidity, the tornadoes (though Ive only seen 3 in 17 yrs looking for them), hail, the allergies are bad for some people certain times of the year, a two party primary, some of the smaller towns can be clannish
Maybe I'll think of more later