Maru has hit upon a sweet spot with its casual reinterpretation of kaiseki (Japanese haute cuisine). With the seven-course meal (which changes monthly) you get a variety of seasonal dishes prepared with the light hand and beautiful presentation associated with kaiseki (but without a terrifyingly high bill at the end).
Maru also has a fancier restaurant in Ginza, with the option of more elaborate dinner courses, and a more casual spot in Shibuya.