A few years ago we travelled to Orlando via JFK around the same dates. We had ample time at JFK but they cancelled our flight to MCO. There were still 4 more flights that day to MCO but all were booked out. Even more so, they could only get us out 4 days later! (also all on Delta). Most horrible experience. We eventually managed to get out of JFK the next morning on standby. But I want to minimize the chances of that happening again. Hence my stress about booking such a tight connection time. But I have been monitoring flights now for 4 months and prizes only keep rising.