Short answer
Don't miss Sete Cidades' twin lakes, Furnas' hot springs and Terra Nostra Park, and the tea plantations at Gorreana and Porto Formoso. Whale-watching in Ponta Delgada and hiking around Lagoa do Fogo are also highlights. Distances are short but roads wind, so plan realistic driving times and check weather before outdoor activities.
General information, not legal or tax advice. Rules and amounts change: confirm with official sources.