As per conversation with BM261945, mhulse36, and ichimori on the server today, I wanted to bring up the idea of building on top of the Nether.
There's a function of spawning dark oak trees which can allow a player to break through bedrock. I looked through a bunch of reports about this effect, and while there is significant controversy over whether or not it should be fixed, it has yet to be addressed. At least one commenter said that it still works in 1.8.1, so I'm unsure as to Mojang's intentions here.
(a report with pictures and comments: https://bugs.mojang.com/browse/MC-10176)
In the end, it's up to Zedwick as to whether he wants to allow it, but I'd like to suggest that it could be used to facilitate building the Nether Network in the new nether up on top where it's flat and open. If allowed, the flat open space would make setting up a rail transport system much easier and more efficient not only construction-wise, but also organizationally.
*I've been told that Zed has said "no" to building on the nether before, so I'd like to clarify that I'm suggesting a particular exception for the Nether Network. Building mob farms and other things up there would be exploitive, but I think it's reasonable to ask for an exception in the case of a transport network.