Considering that a large population of people are affected by colour-blindness, it would go a long way to making the game more enjoyable for us if you take this into consideration when designing encounters and icons that are meant to telegraph information quickly.
For my colour blindness, I have trouble distinguishing small amounts of red or green that are used to tint a colour. A perfect example of this would be the light purple used in the new "malnourished" buff. Since the addition of this buff, it has become much more difficult to track my food duration, as I can hardly tell the difference between it and the regular blue "nourishment" buff. There's really no reason for you not to just make this icon a bright red or something similar.
Another prime example would be the overuse of light shades of orange, green, and yellow, specifically used in raid encounters. It originally took me quite a while to tell the difference between orange circles and green circles, as the light lime-green and the orange both look quite close to yellow for me (the red tint added to make orange, and the green tint added to make lime). This has once again come up with the newest raid wing. A good example would be the river of souls encounter where it can be difficult to distinguish between the colours of the lightning AoEs and the walls of death when they move inside Desmina's bubble. All 3 of these indicators are quite close together on the colour spectrum, and make the encounter even harder for colour-blind players.
Anet does a great job respecting a wide variety of sensitivities, so I'm surprised that things like this make it through the cracks.