We always visit Universal (studios and IOA) during our vacations, and on occasion we also visit Busch Gardens. These are all excellent choices. IOA is incredible if you like thrill rides. Studios attractions are visually incredible. Busch Gardens has a great mix of both thrill rides and animal exhibits, several roller coasters.
To be honest, if this is your first trip to Disney, however, I would just stay at Disney. AK = 1 day, MGM = 1 day, MK = 2 days, Epcot = 2days, DTD/PI= 1day. Some resort hopping is fun too if you get tired during any of that. If you are going in the middle of summer you probably would want to visit the water parks also. (Typhoon lagoon and Blizzard beach)
I would save Universal and/or Busch Gardens for future visits if it were my first time in the area.
Sea World, and Discovery Cove are also great ideas for future trips also.