I'm shocked the day care allows an intact male. The ones around me only allow them up to 6 months of age.
The truth is, the mating behaviors will lessen and aggression towards and from other males will decline as well. I have an intact male, but he doesn't go to day care or socialize with other dogs when I'm not around. I can pretty easily control his aggression and mounting behavior but no one else can. If he was in a day care environment he would not listen to any of the handlers there. Now...if its a female in heat, near heat, just out of heat, the only thing that stops him is a leash and collar.
The health side affects are highly debated...most research will use very ambiguous words that don't tell you the exact increase or decrease in risk for disease a or b. It really starts to depend on your risk tolerance and if a 2% increase in risk is big enough for you to change your lifestyle.
At this point it sounds like you want to continue taking your boy to day care, personally I'm surprised they still allow you to bring your boy there. He's a huge risk for them when it comes to other owners and their dogs. If you want to continue to do off-leash, dog get togethers with other dogs, neutering is something to consider. I used to go to the dog park a lot, my boy grew up, started acting a bit more aggressive, wouldn't start a fight but would finish it. He does have dominant tendencies towards other dogs, which makes other dogs uncomfortable, so we just avoid strange dogs and dog park like areas. It's not a big deal, he doesn't need the dog on dog interaction from strange dogs, but it was something of a lifestyle change because I did enjoy watching him run around with other dogs and taking him to the dog park.
CD RE TC HIC 7/10