Planet Minecraft

Ok, so I'm making my first to-be-published texture pack, based loosely on the game Shadow the Hedgehog (since Sonic texture packs have been done enough already). Anyway, it's going ok, but, I'm not sure what to make the nether (fyi, I made the End the Black comet, and the Enderdragon into Devil Doom). I have two candidates, levels from the game: Lava Shelter and Mad Matrix. The former is a level set inside a technologically advanced fortress inside a volcano, and the latter is Robotnik's (a.k.a Dr. Eggman) computer mainframe which the player is transported inside (the level is very red and stuff so that's why i might put in the nether). Normally i'd do the first, but doing a volcano in the nether would be somewhat cliche, though i'm still leaning towards it. So what are your suggestions for the nether, or for the texture pack in general?
Still looking for a half-decent signature,
Doomslicer
P.S. How do you change the end/nether portal textures and sky background? I know u need custom programs (i use mcpatcher) but what are the file names and dimensions so i can create them from scratch?

Anyone?

I have no idea what you are talking about, unfortunately.
Put it in to human words. xD

you obviously havent played Shadow the Hedgehog

I'll just go with Lava Foundry. Now does anyone know how to make the aether?

I'll just go with Lava Foundry. Now does anyone know how to make the aether?

One does not simply "make" an Aether.

i meant the textures u make. I might make the aether textures into SC-ARK

so... any other ideas for what biomes should be?