Very interesting and enlightening discussion so far. Thank you all.
As to weight, Google says the Yamaha 50 and E-tec 40/50 are 240# and two Honda 20s together are but 16# more (58# over the Honda 40/50) --and they can be started with a lawn tractor battery and charge a remote Optima with the same 40/50HP Honda 10A alternator --each. Besides, they look so fine.
I'll do no trolling, 50% manatee and other no-wake zones, 30% open water, and 20% shallow places with mud and logs. My thought was to go in on one engine and if it were damaged or plugged up, pole or paddle back a few feet, raise it, and lower the other. At mostly speeds that slow, unlike limping home, the props for open water shouldn't be a problem. Besides, they look so fine.
The mention of locating a swim step is a poser. I'd need at least a swing-down ladder mounted way off-center, as I'm no longer agile enough to re-board without one, nor, considering the confines of the V-berth, those other 20-something twins.... Damn, they looked so fine.