How many days would be ideal for a visit to Redwood National and State Parks in California to fully explore its main attractions, enjoy hiking and outdoor activities, and take in the stunning natural beauty of the redwood forests, coastlines, and wildlife? Considering the park's vast size and diversity, what is the recommended amount of time for visitors to experience the highlights without feeling rushed, and how can the duration of the trip vary based on individual interests and the specific areas of the park one wishes to explore?