Hi Mike, I guess I can toss in a little local knowledge! First, you probably know that early March is right in the “rainy season” of the Central Coast of California. Some years that means no rain at all, but others it can involve heavy rains, even floods, and sometimes mudslides and closures (temporary or months-long) of Highway 1. So, follow the weather and maintain some level of flexibility. I don’t know your budget but there are a modest variety of lodging possibilities between the Carmel area and the Cambria area. Rates might be lower in March than other times. At the top end is the elegant but rustic Post Ranch Inn in Big Sur, often listed among the best resort hotels in the country. After that, nearby Ventana Inn is very nice, a little further south are more quaint River Inn and Deetjen’s Big Sur Inn. Also a lodge at Ragged Point further south, and a few others. Various campgrounds as well, if that’s your thing, in March.
In Monterey, the Aquarium is excellent, but yes has become quite pricey, so if you go, dedicate enough hours to it to justify the expense. You can have lunch inside there. You might find that some local hotels or inns have special offers that include aquarium tickets, or they might have guest passes or discount coupons. At least ask.
They charge quite a bit now to enter the private 17-mile drive, but if you eat at one of the very good restaurants at the Lodge at Pebble Beach or Spanish Bay, or play golf there, I believe they still refund your entry fee, ask when you pay the fee. It’s a lovely drive especially if you are a golfer, as you can stop and see Pebble Beach, Spyglass Hill, Cypress Point, Spanish Bay, and other courses, and stop at the pro shops, etc., along the way.
And yes, Point Lobos just south of Carmel is a beautiful state park, right on the coast. Ansel Adams called it the world’s most spectacular meeting of land and sea, or similar words.
Hearst Castle is over-the-top, but a unique and fun experience, also requiring a pricey ticket and a number of hours. They offer 3 different tours at the visitor center, I think one is most indicated for first time visitors, and they all include bus transport from the visitor center up to the “Castle”.
Yes, the views down the Bug Sur Coast can be wonderful, at different times of day and in various weather. So stop at many, or all, of the view point areas. They are cracking down on the dangerously congested parking in some areas not suited for parking, such as near Bixby Bridge.
Here’s a local’s tip, a stop most of my visitors find especially memorable. Driving south, about 11 miles south of the Carmel River Bridge, and just past the entry to the Rocky Point restaurant, take the left (away from the coast) on Palo Colorado Canyon Road, with the idea of driving slowly east a couple of miles, then turning around where the road finally widens with a bunch of mailboxes nearby. This is a very surreal experience, a dark, curvy residential road, lined with redwoods and other large trees, houses up on stilts, very different than the bright light of the coast. There are no food or shopping stops possible in there, maybe a few photos, and it should be maybe a 20-minute detour along your coastal drive.