Give hostile mobs variations that make them gain health or damage

Hostile mobs are great but besides for charged creepers, husks, and strays they always do the same damage and have the same health, it would be nice if they could spawn with more or less health and/or attack points. The variation could be something from color to clothing, but each specific variation always does the same damage and has the same health, allowing the player to know what mobs to avoid (for example, a red creeper will always have 3 more hearts then a regular creeper but does 5 less hearts of damage). It would also be nice if the variations that are better spawn less on easy and more on hard and vice versa with worse variations