I'll offer some thoughts on the flying side. I will only get nervous about flights if my route has a very limited number of options per day, even as low as one per day, e.g. small airport to small airport, but PHL to MCO shouldn't be an issue. I tend to try to fly the big three airlines as a way to reduce this anxiety, knowing I could potentially get on a later flight should I need to. I also typically book flights departing earlier in the day, and I track my flights (including any connections) and the inbound aircraft(s) using Flightaware. This can often help me understand if there's been a mechanical delay (which can lead to delay-delay-delay-delay-cancellation) or a weather delay (which will usually resolve eventually unless it's a major storm like a hurricane or nationwide). If there's a mechanical delay, I will try to change my flight to the next available to make sure I can get a confirmed seat. If it's a weather delay, I typically wait it out.
These are just the ways I can feel like I have control over a situation, but honestly I rarely have to use this skillset. Out of 29 flight legs this year, two have had mechanical delays where I've asked for a seat on the next flight, one was cancelled and I was rebooked to the next day, and the other 26 were normal.
Then there are the technological glitches that you can't really prepare for, like the Southwest incident over the holidays or showing up to an airport and the entire airlines computer systems are down! They are pretty rare though and I wouldn't let that concern prevent me from booking a flight, particularly if it saved me 15+ hours on the road and an additional 10+ hours in travel time each way.
