The better solar panels will do better than that, of course only when the sun is shining. See this link for good solar advice.
Solar Power on Boats | Adrift at Sea
As sailingdog says, he really never has to run the engine to charge his batteries - solar takes care of it. And I bet he runs more electrical items than you will. You should be able to get all your amps from a solar panel of a reasonable size taking into account your planned electrical items.
For the distance you're going to travel I'd certainly take a good wind vane which will take care of 98% of your steering as you're not going to power long with the fuel you could carry on a 26' boat. I'd probably throw the generator overboard out of annoyance. Besides you can't easily fill the fuel tank in rough weather, when you need the self steering the most. As well the tillerpilot will not use the miniscule power the specs say when it has to work hard.
Here's a link to what I think is a good fairly affordable wind vane.
NORVANE Self-Steering Wind Vane. Stainless steel, servo-pendulum. Powerful, sturdy and reliable for sailboats 20’ to 60’
If you already have the tillerpilot I think it will be of some use when powering in calmer conditions but I don't think it's up to steering offshore in all conditions as a good vane is.
Brian