Not bad bikes you have found and the choice will be up to you. They will all be good.
BUT_________ at 200lbs you may have a problem rear its head in the not too distant future. The bikes will take your weight and not cause a problem. The BUT is the wheels. Stay away from Low spoke count wheels unless they are warranted fully by the shop. Go for 32 or 36 spokes and you should be fine.
The Giant Defy and Rapid. Two similar bikes except for the Ride position. Basically the same bikes except for the Bars. If you plan on some more serious road riding- I would go for the Road bike in the Defy. If you "KNOW" you are going to enjoy more casual riding- then the Rapid may suit you better.
And That 20 miles max 40 may go by the board if you train a bit more and see the Weight loss and feel the fitness cycling can bring.
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How long was I in the army? Five foot seven.
Spike Milligan