Did a quick check with Budget (DIS people recommend them). I used no discount code, just regular rates.
Pick-up 9 am; drop-off 3 pm for both ways
Two prices for each: pay at counter or (pay now)
P/U Cape Canaveral - Return at MCO
Compact/Ford Focus 74.99 (67.49) with taxes/fees 83.05 (75.10)
next size up about $2 more
P/U and Return at MCO
Compact/Ford Focus 73.99 (43.88) 93.01 (57.73)
* this rate was showing you needed an overnight Friday (despite that I put it in as a Saturday pickup and return) - the Cape Canaveral rate didn't have this stipulation
To get a rental car in Cape Canaveral, we collect your luggage and go outside the ship, stand at the curb in the corral for our specified rental car company and take their free shuttle to the office. They automatically come to the port for pick-up, no call needed. After that, you are on your way. You will have to pay any tolls between the port and the airport, so add a few more dollars to the car price - and whatever gas it would take to go about 45 miles - 2 gallons? at $4/gallon - so that adds $10 to rental price.
Looks like
DCL + MCO rental = $75 + 57 ($133) vs $85 for Cape C rental. Is it worth $48 to you not to have to schlepp luggage from ship to car, car to airport and turn it in? Each man's personal decision (well, not in your case - two men have to agree).