a solar dehydrator
would work well, though I would design one that didn't expose the material to be dried to the sun. a solar air heater feeding warm air into an old freezer or refrigerator has worked well for many folks.
berry products could be juice or jam or syrup or tea, as yukkuri_kame mentioned. maybe baked goods. give it a little brainstorm and I'm sure you could think of a few more. young mulberry leaves have a lot of protein in them, so maybe something along the lines of a protein drink. keep in mind that selling processed food will likely require a licensed kitchen, unless you'll be selling through less official channels. commercial kitchens can be rented in many places, though.
milk and cheese could work well. again, there will be some extra equipment and licensing costs. eggs are easy, and chickens/ducks/et cetera
would be great complements for your fruit
production. herbs and vegetables would be great, too, if you're clever about it. the labor involved will likely depend on the condition of the dirt you end up with.
you might connect with some experienced permaculturists and teachers to host design courses on your land. might not be much income, but you would have the advantage of multiple perspectives and extra hands while you're getting established. there are plenty of other ideas for income in this farm income forum, too.
as long as you're on the "superfoods" track, you might try growing chia (Salvia hispanica
), too. you could give maca (Lepidum meyenii
) a try as well, though that might be more of a crap shoot. supposing they crop, both of those are annuals and would potentially yield your first year.