What is the recommended Way to randomly Place Terrain Tiles of Varying Sizes?

I using Blender to make meshes I want have tiled in an array to make the world map. Instead of fixed world map, I want to have some randomness to the arrangement of the tiles. The problem is that certain assets will need to be larger than a single tile, and rotated by increments of 90 degrees. The meshes are designed to line up regardless of rotation.

My PC is not able to run UE5, so I am working with version 4.27.2.

The world map is quite large and designed to wrap back around on itself, so I also want to be able to only load the tiles within a given range of the player. While it will be easiest to design the larger tiles as a single mesh object, I am not so sure about if I should leave the larger tiles as a single object, or if it would be better to break them down to the size of the smallest tile since the tiles are power of two multiples of the smallest.

Since I can see issues possibly happening with both methods, I figured I would ask the community what they recommend.