You will need to be smart to avoid crowds, but it can be done.
You will be there during Gay Days, and the "featured park" will be busy--I know it is MK in Saturday, but I don't know the others off hand. You can do a search here, or do a web search for Gay Days and you will find the schedule.
Make sure you understand how FastPass works, and use it.
And all the usual stuff--eat at off times, get to the parks early, get seats early for parades, don't rush out at park closing, etc.
Somewhere I read that Gay Days features lots of late night parties, so the more early morning activities you can schedule, the better.