If you ask me what is the funniest Adam Sandler movie ever made, I'd say Happy Gilmore without second thought. I have always hoped there would be a sequel to this classic film, but we'll probably get Grown-Ups 10 before Happy Gilmore 2. Adam hasn't done sequels to any of his early work, which many would say was his best work. Maybe it's a personal thing, maybe the price is wrong, I don't know what's holding him back from re-visiting classic characters.
It would be great to get more Gilmore. I love sports comedies and would like to see more of them made. But I don't think HG2 would work particularly well as a normal motion picture. I'd love to see it done as a mock documentary, or Mockumentary. What if Happy Gilmore had been a real golfer who actually won a Tour Championship back in 1996? What if 20 years later, ESPN did a 30 for 30 documentary about him?
There are several different directions you can take it, depending on what Sandler is willing to do. Perhaps Happy Gilmore now has a teenage kid (bi-racial offspring with the Asian lady he slept with in the first movie) who is a golf prodigy who just won the 2016 Waterbury Open. Happy either could have had a great career with multiple major championships, or perhaps he flamed out shortly after winning his only gold jacket. If Sandler is cool shooting new golf footage, that's awesome. But it could also work if all of his contributions are in interview format.
You could include a 5 minute "sport science" segment about how the Happy Gilmore swing was effective and nearly impossible to replicate. There could be other golfers on the Tour who ruined their careers trying to master the running start swing. Do interviews with characters from the original movie. Shooter McGavin's interview could be conducted in a padded room. Do interviews with real golfers telling fake stories of what it was like to play on the same Tour as Happy.
You don't even need a script. Just film a whole bunch of interviews and get the actors/golfers to improvise. Only include the best clips. If there is any unused golf footage from the original, find it and use it. Use CGI where necessary. Film as much new footage as possible with other people attempting the running swing, right from novices to professionals. Part of the story is about how he became a cultural phenomenon who fans still love 20 years after he started.
I think this should be made by a real documentary film maker who is a fan of this movie franchise. He or she can take it in whatever direction they want. Pretend it's real, but it isn't. This would be perfect for a Netflix release. It would cost very little to make and fans would love it.