Congrats! My wife and I also took a belated honeymoon to WDW. We stayed at Pop because we were very short on cash at the time but wanted to spend time in the World. Now we both have better jobs and more steady income so if we were planning it now we'd probably go with POR. We still had a really great time at Pop; whether it's worth it or not to upgrade comes down to how much time you're going to spend in the room/at the resort.
Definitely call to note your honeymoon on your reservation (or tell them when you make the reservation if you do it over the phone). The front desk should have buttons waiting for you, you'll probably be placed in a more secluded room for privacy, and you might even get an upgrade or in-room surprise.
Definitely book some nice ADRs outside of the parks. I love California Grill and we are trying Jiko this trip. I've also heard great things about Narcoossee's, Citricos, and of course Victoria and Albert's if your budget can handle it (this one is on my Disney bucket list but I don't see it happening for several years!). Sanaa is also a nice choice and you can see the animals outside during lunch.
If you are into tours, there are choices ranging widely in time commitment and budget. We liked the Behind the Seeds tour at Epcot and it costs around $20/person. Some of the tours specifically have a minimum age so you will be with mostly adults.
I always like resort hopping on WDW trips. You can visit the deluxe resorts (and others mods) to eat, shop, look around, and dream about where you'd like to stay on future trips.
Are you drinkers? It can be fun to drink around the world and around the monorail. There are also events like the Jiko wine tasting (haven't done it yet but hoping to soon!) that will definitely be adults only. I also liked the Illuminations Sparkling Dessert Party to have a great view of the fireworks as well as unlimited sparkling wine and desserts.
Whatever you choose, have an amazing time!! There are so many choices!
