You picked the right island, beautiful and romantic. Must dos are Waimea Canyon, Kokee State Park and Kalalau Lookout
on the SW side. On the South side, where you are staying, is the Spouting Horn and the National Botanical Gardens. The Fern Grotto cruise (touristy but worth it), Wailua Falls, A Pacific Cafe (upscale restaurant but not dressy), Opaekaa Falls, and Old Kapaa Town are on the West side. The North shore is the lush wet side of the Island with magnificent beaches and bays. It has the Kilauea Lighthouse and bird sanctuary (great bakery in Kilauea), Princeville Hotel (a good place to view Hanalei Bay while having lunch on the deck), Kee Beach, the wet and dry caves, and the hiking trail to Na Pali Coast. Things to do: Helicopter ride, best out of Princeville. Catamaran cruise of the Na Pali coast. Duane's Ono Char Burger. Savor a smoothie at Mango Mamas or Coconut Ice Cream at Lapperts.
There is much more. Keith

Yes Kauai the most beautiful place on earth! We went for Christmas, and stayed in Princeville at a wonderful condo. Be sure to visit Hanalei bay, we also did the dinner cruise sailed along the Napali coast absolutely fantastic experience. We also went on a kayak adventure up the river and a hike to a secret waterfall. The people the island the atmosphere if life was a little less complicated I would pack my bags and move there in a heart beat! Enjoy your trip what a fantastic place to honeymoon!

Its been awhile since I've been here. Just wanted to say how amazing Kauai was!
We took the Kauai: Revealed book with us and just enjoyed little out of the way things, like Queens Bath, Kipu Falls, Sealodge Beach. We ended up leaving Poipu after a few days because of construction noise and heading north to Princeville. I'm SO happy we did. Loved that even more. The people are so amazing and laid back. Such a great vibe.
We did a helicopter, dinner cruise (Na Pali coast, AMAZING), luau, Pearl Harbor and drove all around Oahu. We are definitely going back some time. The north shore of Oahu had some beautiful beaches, the most gorgeous i've ever seen and the softest most wonderful sand! I still dream about Kauai once in a while, what a true paradise!