The thing with their previous templates is that they were BAD. If they want to give us templates, they need to put more thoughts into how people actually USE Wild Shape.
First you have the Combat forms. I think these can be roughly divided into three different builds, with focuses on bulk, damage or disruption (like a giant spider's web ability or a giant frog's ranged grapple), but maybe that would be part of an additional layer of customization I mention below.
Then you have the spying/scouting forms, which are usually really small and innocuous types of animals with some form of traversal ability, like wall climbing.
And finally you have travel forms. These grant you ways to traverse the land, either through additional speed, the ability to swim or the ability to fly.
Each of those templates would then be further modified in some ways probably by picking up traits from some sort of list, maybe themed after types of animals, with some subclasses granting you new traits you can pick up (the Moon Druid, for exemple, would allow you to pick 'Predator' traits that grant you more powerful attacks). Basically, you'd have a few basic stat blocks with additional themed templates on top.
To me, this is a much better way to do it than 'land/sea/air animal' or whatever.