- increase contrast (darker darks and brighter brights),
- add colour grading (blue in dark areas, warm orange in lighter areas),
- and make sunlight warmer at dawn and dusk.
I would still like to see effects like bloom, dynamic lighting, and water reflections, but these things too complicated for my current knowledge of MT and Irrlicht.
EDIT: This effect may look better with a higher gamma value, such as 2 or 3.