With some help I have been working on a temple of sorts (can't really think of anything better to call it). The build has been completed in survival mode, so yes I did die by lava more then once. Let me know what you think, if you have any suggestions I would like to hear them.
Looks like a nice start. Maybe some embellishing will help. Some netherbrick fencing and maybe some lit netherrack? Some soulsand would look cool too. Slap a portal in it and its your new nether temple.
Yes, I definitely agree with the fence/soulsand. I used both of those with my Dark Pagoda, it seems to go with the feel very well, and the Nether Portal is optional...but if you do, I recommend hiding it and using sticky pistons and switches to open/close it, just to make it more integrated into the structure.
Maybe make an obsidian/stone design in some walls so if you pull a lever some stone is pulled out of one of the obsidian designs and you need but light it...
Netherbrick Temple, featuring lava phoenix