The small Yamaha outboards have not kept up. I recently replaced a Yamaha 20hp on a Boston Whaler with a Suzuki 20 and couldn't believe how much easier starting, smoother and quieter the Suzuki is. And a lot of the Yamaha reliability "legend" is for the Enduro models that are not sold in the US for EPA reasons. They are everywhere in the Caribbean.
I'd go with a Tohatsu 6HP Sailpro with the extra long shaft that rgranger has. It only weights 55lbs and comes with an alternator to charge the batteries. Going up to 8hp adds almost 30lbs for little power difference and the shaft is shorter (the 9.9hp has the extra long shaft) The long shaft will let you mount the outboard bracket higher so you don't have to lean so far over the stern to reach it. The Sailpro also comes with a propeller meant for heavy boats at low speeds rather than small planing boats. A standard high pitch propeller meant for a RIB going 20mph is useless on a heavy sailboat going 5mph.
Be sure to ONLY put ethanol free gas in the outboard - which is readily available in the OP's Florida. Small carbureted outboards do not do well on ethanol and the jets eventually clog. No amount of gas additive or carb cleaner will really help. You have to take off the carburetor and send it to a shop for an overnight ultrasonic cleaning - or it's often cheaper to just buy a new carburetor.
If the OP lived in New England where it's almost impossible to find ethanol free gas, I'd recommend going up to the Tohatsu 9.9 with the extra long shaft and fuel injection (EFI) instead of a carburetor. Fuel injected outboards are much more reliable in places where ethanol fuel is used. I believe Tohatsu is the only company with a fuel injected 9hp. If the OP is concerned that the 6hp is not enough and doesn't mind the 30lbs, he might want to look at this engine. Starting an EFI engine is like starting a modern car engine. No choke to fool with. It just starts.