I need help deciding how to create my 512sq km world

I thought of using 8 tiles of 8x8, then either import them using the convention:

  • map_x0_y0 / map_x1_y0

  • map_x0_y1 / map_x1_y1

  • map_x0_y2 / map_x1_y2

  • map_x0_y3 / map_x1_y3

Alternatively, I can stitch them together in photoshop and then import the full map together.

Also, if my specs are not enough for this 1:1 map, I could scale it by 2. So I would be fitting 16x32 km into a 8x16 km space. Then I could make two heightmaps:

  • map_x0_y0
  • map_x0_y1

Is this viable?