I've found that early tours/B'fasts on the monorail loop resorts or the MK is doable. There's the boat that leaves for the Contemporary that starts ~6:45 AM. From the Contemporary you can then take the monorails to the resorts or MK
The problem comes with hitting Epcot or AK early. They are supposed to have an early Breakfast bus, but I don't think it's entirely reliable. It's been a no show for us before, but thankfully FW provided a van to drive us over to EPCOT after the bus never arrived.
I'd say for AK/EPCOT, your best bet may be a taxi.