Should be a retractable dome like in Toronto where the Blue Jays play baseball. Then if it's a nice day, the dome is back and it's sun and fun and if it's raining, close that baby up and golf in comfort.
Of course a dome that size would be like that place they built in the 1980s or 1990s for that group of people to live in for a year without living. Can't remember the name of it - just know that it turned out to be kind of phony. Hey, maybe we could buy one of those (I think there were 2 separate sites) up and convert it into a golf course. We might need one of us to win on The Apprentice though to get the financial backing.
Back to reality - I'd also like some interesting sand trap setups too ... how about some quicksand

for those really bad golfers who are holding you up on the course?