DPS - 100 hp, no avoid/mitigation, soft CC, 10 dps
Tank - 150 hp, some avoid and mitigation abilities, no CC, 5 dps
Healer - 100 hp, no avoid/mitigation, no CC, 5 dps, 5 hps
CC - 100 hp, no avoid/mitigation, hard CC, 5 dps
Oh look. 4 different classes, whipped up in the span of 30 seconds, that are balanced in 1v1 encounters but without having the same capabilities.
If I thought about it for 40 hours a week and had 50k/year motivation, I guarantee I'd be able to expand that to balance WoW around 1v1, flawlessly.