Re: solar recommendations
The rule of thumb is you can expect a solar panel to make roughly 30% of it's rated wattage as amp hours.
That means a 100 w panel will make you 30 ah of usable power per day. That 50w you are eyeballing will make 15 ah. That's on a good day.
Your autopilot alone will need more than that offshore.
My good friend has a Bristol 24, I'll not advise on the feasibility of taking it off shore but I'll recommend you look at mounting solar on the fore deck, over the sides etc. You will need more, and can almost never have enough (well, don't come off looking like skylab).
Lessons learned are opportunities earned.