If I recall correctly, you could adjust the brightness on the VT 100 series through one of the setup modes. The VT200 had choices other than green. The TRS-80 Model 4 had white and I used a 4p as a terminal to remote mainframes and minis. The Xerox 820 was white. Most of the early Apple/IBM PC monochromes were green, but there were some really nice amber third party monitors.