Well, I believe the act of getting on top of the Nether to be more of a glitch than a cheat. Because if you think about it, Mojang has placed bedrock as the roof of the nether to prevent players getting above it. The only reason why we can get onto of the nether is by conducting glitches. Eg The Enderpearl method is a block glitch, And the old method of growing the trees is also a glitch because it wasn't a intended feature.
Also on the topic of Gold farms. I don't think The Server will like a gold farm, I currently Have a Very Efficient gold farm on SMP that will lag the crap out of the server, So if we were to build a gold farm above the roof of the nether it will make the server lag even more because the farms above the nether are Usually More efficient than the one in the overworld.