What kind of gameplay are you aiming for?
The scale of content required in order to keep the map interesting changes depending on the player's unit count. If it's an RPG or a fixed force, the visibility of the map is low, and it can feel daunting if the player feels they have to cross a vast open space that's not really going to contribute to their gameplay. This means that you'll need to make the map quite detailed in order to maintain interest.
As far as I'm aware, Ludakris sized maps with a large amount of objects can really tank performance because HD isn't well built to handle it. You'd have to be a very skilled designer who carefully controls what areas of the map have activity and what don't, based on the player's movements - This can work in a linear map, very easily, but on a Ludakris sized map you're more likely to go for big open areas so you aren't spent detailing every pathway for the next 5 years.
If it's a more typical game with base-building involved, then giving the player large open spaces and a more strategic landscape is benefitial, they'll naturally be overseeing a large area and they'll prefer to see the lay of the land. The player's attention will be split as they oversee their base, so they'll care little for the detail of the environment and more on the strategic aspects and what possibilities the map presents.
Perhaps you could experiment with Trigger Studio and create a map between Giant and Ludakris, but I haven't experimented with that. For me personally, even a Giant sized map is a daunting prospect as I like to make mainly fixed force/RPG/Multiplayer scenarios.