I have been to the El Dorado Royale, and it is AMAZING. Hands down the best food and service I have EVER had at an all inclusive. There are tons of restaurants to choose from, you can eat somewhere different almost every night. There is also a Martini bar! All of the indoor restaurants are air conditioned too, which is awesome. The service everywhere at the resort is wonderful. The pools are wonderful and many rooms have swim-up suites. The resort offers bike tours, or bikes that you can take out and ride around the resort. The resort is quite long, so there's lots of area to bike or walk. There is a big green house behind the resort that you can bike to also. EDR grows many of it's own vegetables and herbs right on site! The only downside is that the ocean is a bit rocky, and there are huge sand bags in the ocean. The sand bags are placed to help the environment. (I have noticed these sand bags at other resorts in the Riviera Maya also) There are areas that are fine for swimming, but not as nice as the beach in Playacar/Playa Del Carmen, or Punta Cana, for example. I guess it all depends on what you are used to. If you are not a "swim in the ocean" type of person it doesn't matter to you! If you really want to splurge, book a room in the Casitas - so amazing, much more private and super romantic!
My husband and I went to the El Dorado Maroma for our honeymoon (a sister resort) and we were given a few perks (for free) for our HM. We had a wonderful breakfast in bed, dinner on the beach, discount at the spa. I think there were other perks, but I honestly can't remember. We felt very spoiled at the EDM, the most romantic honeymoon we could have asked for! Wish I could go back to either resort!
We were married at the Now Sapphire, just down the beach from the Excellence. I walked by the resort on the beach and it looked amazing. The beach there is very nice sand. Lots of lounge chairs!
Hope I was of some help! I don't think you can go wrong with any of those three resorts!