I'd go volunteer the 30 days at the horse riding ranch on Espiritu Santo (Vanuatu). It is divine there!!! Spend my days helping with the horses, riding along the beach and through the blue pools at sunrise & sunset. Swim, kayak and dive.
The local markets at Espiritu are amazing with fresh organic produce and there is great little shacks next to it where the locals cook the produce and fresh seafood caught that day for you.
Exercise, animals, volunteering and fresh organic produce......my dream whole 30 holiday!!!