My top choices for romantic getaways are AKL, BWI, WL, and GF in that order.
The atmosphere at AKL is the most romantic of al the hotels in my opinion. It feels so exotic and cozy and the views to the savannah from the balconies are so lovely. The Victoria Falls lounge is also very romantic with great drinks. Jiko, Boma, and Sanaa are also some of the best dining locations on property. The seating areas scattered around the property also offer great "moments" whereyou can relax with your spouse.
I also find Boardwalk to be a wonderful romantic getaway location. The rooms are well appointed and there is so much to do there. The lounge at the BWI is also a perfectly romantic spot to spend time with your spouse. The porches also have lots of rocking chairs to sit back and relax on. The Boardwalk also has its fair share of nightlife with Jellyrolls and the Atlantic Dance Hall. There are also street performers out at night and the Surry Carts you can rent and ride around the lake.
The Wilderness Lodge is also a romantic contender, but it lacks the uniqueness of the AKL and the abundant nightlife of BWI. It is so cozy though that it makes you want to snuggle up with your spouse. The food at WL is also pretty good, but not exactly "romantic."
Finally, though I have yuet to actually stay there, the GF is a big contender as a romantic destination. The phenomenal restaurants and abundant shopping available on this property make it a tick about the rest. There are plenty of romantic choices as far as meals go. There is also a full service spa in the GF and that can elevate a Disney getaway to a whole new romantic level! The feeling of the lobby may not be as intimate and cozy as the priviously listed hotels, but it is still quite beautiful and "grand" ha!
Hope this all helps! You can personal message me if you would like further input