Day 1: morning Oriente → Royal Palace (first slot) → Austrias (Plaza de la Villa, calle Mayor, Plaza Mayor without lingering); afternoon through Sol and Gran Vía/Callao; evening Debod at sunset and dinner near Plaza de España, Conde Duque or your stay — skip Debod at midday.
Day 2: Prado at opening with a booked ticket — selective visit, not a marathon; lunch Letras or Ibiza, afternoon Retiro; evening Letras/Huertas and optional Cibeles–Alcalá stroll; second museum: Thyssen over Reina Sofía unless you are really there for Guernica.
Day 3: Malasaña and Conde Duque; El Rastro only if it is Sunday and you go early; afternoon Chueca/Salesas or calmer Chamberí; last dinner near the hotel — do not cross the city for a trend.