We generally try to avoid the use of colored lettering in articles because it can be confusing and an eyesore. I think that the "confusion" aspect would be especially a problem with Destiny, as there are a number of different elements of the game that use color coding. For example, special weapon ammo uses green, as does uncommon rarity for all items. As you noted, Void damage is purple, but so are Legendary items AND heavy weapon ammo. Unless it really adds something useful, I would be hesitant to begin putting colored text into articles themselves.
With that said, though, I'm not sure I can envision what you're suggesting. Can you get a little more specific? Where would these color-coded letters be used? In what kinds of situations? How would it translate to other articles about other things that aren't weapons?
For weapon rarities, the colors that go with the weapons go within the text. So if you were describing the Nox Cantor pulse rifle, you'd input: "the Nox Cantor is a " (rarity link|uncommon) pulse rifle." Note that those parentheses would be brackets.
That brief piece of code would translate into being green text, or whatever the text would be. For reference, check out this article from the Borderlands wiki (a place where I put my organization to particular use): http://borderlands.wikia.com/wiki/Conference_Call.
Besides, would the issue of having two elements being more than one color really be an issue? To refernce the Borderlands wikia again, we've handled it quite well. Purple-rarity weapons in BL2 have the same text coding as the slag element. However, the green rarity weapons were green, while the corrosive element was handled with a significantly darker shade.
Destiny is very similar with weapon colors and their coding, so just give it some thought. Nothing wrong with being too organized, eh? :)
Thanks; T3CHNOCIDE and I are talking it over and we'll give some thought around how we'd want to implement something like this. We both agree that putting color into the text of articles themselves is likely to be distracting in a way that takes away from, not adds to, the content, but we'll look around at some other possibilities for infoboxes, headers, and footers to add this kind of color-coding info. Hopefully we can land on a plan that takes into account all of the factors on the wiki quickly and implement soon. Thanks so much for the thought! :-)
T3CHNOCIDE did upload a rendered image of the solar icon awhile back. I was thinking maybe someone could produce a template like the one below for the "attack" field on the weapon infobox.
And it'd look something like this:
But, of course the text would be better aligned with the image, and the second parameter on that template would also have the other two weapon elements, arc and void. So when the second parameter is filled in, the image corresponding with the respective element will appear, along with the color associated with that element for the text.
Nice, I like that. Let's hang on until Beta to see exactly how these numbers/statistics work for a particular weapon/armor piece. In running through the Resource Upload, I noticed that several weapons and pieces of armor with the same name have variations in their damage numbers and other perks. For example, see 12:45-12:52 in the Resource Upload, where there are two Galahad-B rifles for sale from the Gunsmith, but they have different minimum levels and damage statistics.
If weapon stats aren't fixed, it seems possible that some might have different elemental damages too. We should sort out how all this works before making template changes that might end up being moot :-) And I think that means we need to spend some serious time researching this when the Beta rolls around (and possibly beyond)!