There are adjustments you can make if you think it's too wide. Simply screw the spacers in a little more.
It's supposed to have air coming under it. As long as the actual hook latch is there, it's not going to fly up.
Note that I've HAD that happen to me - hood fly up while driving on the interstate. Circumstances were special - car had been in the body shop for hail repair, and they simply forgot to put the actual hook back onto the hood when they reassembled it. Because Oklahoma is so windy (Texas blows and Kansas sucks), there was a strong enough wind that while I was driving north on I-35 that nothing happened. Turned east onto I-40 to go around a traffic jam and about 2 minutes later, WHAM! Hood flies up, windshield smashed into a million pieces, lots of shattered glass in my lap, and ZERO forward visibility. Simply hit the flashers, started slowing down, used my rear view mirrors so I could see the lane markings and got it onto the shoulder without further muss or fuss, just had to roll the drivers window down and lean my head out to make sure I didn't hit a bridge abutment.