You can go a bit further to get significantly higher color depths using ASCII block characters 176, 177, 178. By using the foreground and background ANSI colors and blending them by using these three characters (25%, 50%, 75%) you can achieve some quite realistic images. If you're more interested in resolution, using half block characters like 220 and 223 can allow you to double your vertical resolution at the cost of not being able to use the color trick.