Most couples start with a list of places and end up overwhelmed. A better starting point is a feeling. Do you want to do nothing at all, or do something you will talk about for years? Both are good answers, and they lead to very different trips.
Rest or adventure?
If you are exhausted after months of wedding planning, choose rest: an island, a lake, a villa with a view and no schedule. If you are energised, choose somewhere with something to discover, such as a city of lanterns or a savannah at dawn. Many couples split the trip, a few active days followed by a few slow ones.
Mind the season and the travel time
Every destination has a best window. The Maldives is at its driest roughly from November to April, Santorini is lovely from May to October, and Bali is generally driest from April to October. Check the flying time too. A twelve-hour journey right after a wedding is rarely romantic.
Decide what matters most
Pick your top two: privacy, food, scenery, culture, or a particular experience such as a sunrise balloon. Let those two choose the place for you. Everything else is detail, and details are easy to fix once the destination is right.