ASCII actually helps, I think. If you try and have a 100x100 grid of fancy graphics it becomes mush. To fit that number of tiles on the screen you need to go symbolic. And most people have highly trained symbol-recognition systems for ASCII.
I agree, you can squeeze in much more info onto the display. I wonder if adjusting colors would help the player prioritize visual info too. like if the terrain was less saturated so that it was even easier to parse the troops and such. OVerall this was so fun to experience.