Maybe a small pumpkin patch in fall? That might fit the farm vibe and would bring in good money. Sunflowers in summer? Not much g but pretty, and they give you seeds to replant. Blueberries are forest-friendly, easy, good money esp if you have some jars. Strawberries in spring? Also fits with the forest in my mind, good money and easy. Flower farm with bee houses? Pretty, decent money, might fit with the small farm in the forest vibe, low maintenance once the flowers bloom, presents for villagers.
Also, once you make enough money and carry out a couple of quests for the wizard, a Junimo hut is an option. Not good for the flower/bee farm, though, they will pick the flowers before you get the honey, unless you place the hut well away from the flowers. You do need some crops to see the Junimos but they are pretty fun to watch in the morning.