I meean, I'd actually say being able to avoid the pitfalls of Wish accidentally backfiring due to poor wording falls more on Wisdom than Intelligence. But that's neither here nor there. To answer the actual question, its pretty simple: I allow the entire table to chime in when someone trying to properly word a Wish spell. It goes from a single player to a sort of puzzle that the entire party joins in on. And I'll give them certain hints, nudges, and occasionally remind players about how the rules of the game work to help the player close loopholes or issues that I see as glaringly obvious.
Sometimes it works out and the table is able to come together to make a near airtight Wish that leaves me with little to no wiggle room to give them a detriment. Other times, the players will either miss something or forget to add some details that allow me to mess with them.
As for the DM vs Player aspect, I do a few things to help ease that. Helping the players avoid a couple of pitfalls really helps to diminish that feeling of DM vs. Player. I also make sure players know how I run Wish. I warn them when they first obtain Wish, and warn them again when they're planning on casting Wish. I also give the table as much time as they want/need to come up with a well worded Wish.
...Ok, I can see why that would turn you off of the wording for Wish. Most wishes I deal with are a few sentences long at most. I've never had a player bring a 20 page contract for Wish. DM should have absolutely read that after the game.