Interesting topic, but, truly, the only way to get huge amounts of gold is from other players, to my experience. Selling, running them, perhaps doing some other service, like questing, ect, is a good way to get yourself some gold. There is no area, to my humble experience, which drops insane amounts of gold in PvE format - sorry...
It is interesting to hear about the PvP HoH victory prizes, which is an inscentive enough for me, which I believe can just as well be attained by using a PvP character, sprucing him/her up a bit with unlocked goodies, and just having good amounts of skill.
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And, lastly, a small correction...
15k armor is NOT equal to Fissure armor. What you have in mind is the slightly more "show-offy" 15k armor, as it is accuratly called, that can be gotten from M.'s Grotto or Granite Citidel. Now FISSURE armor is another story, sometimes costing as much as a Million gold for a complete set, being dragged up by (now falling) ecto and shard prices. A single piece requires about 60 of each, I believe, meaning you pay:
Original Price: 15k
+ Material Prc.: ~15k (or so; not up to speed on costs of different armor "specialty" crafting materials)
Shard Price: 60 x ~3k = 180k
And... Ecto Price...:60 x 7k=420k
And... LOTS AND LOTS OF PATIENCE... equiavalent to an infinite amount of gold.
Which adds up nicely to... a lot... Although... my math is almost surely skewed, as I am not sure about the Ecto/shard need for each piece
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