I'm also looking for PHL-MCO. Cheapest flights on AA or UA are around $250 per person with crappy times and then I still have to pay for my bags. If I wanted the times I prefer it's around $350-429 pp round trip.
I'm hoping to get do under $250 pp round trip on SW and not pay for bags. Right now some of the Saturday's in the summer are pretty high priced for just one way.
I like non stop flights. We like to leave early morning and come back home mid afternoon . If I can't get those times at a reasonable price on opening day with SW out of PHL I have no issues flying out of BWI. They have about 10-20 flights per day and they range around $115 for good non stop flights.
I'm 20 minutes from PHL and 90-120 minutes from BWI. I would have to pay to park at PHL at about $8 a day. I can stay overnight at a hotel in Baltimore for about $100 and park my car there for free.