Bruno Heller said that it was very important for Partridge to die in the first episode, but i haven't find out a good explanation of this yet. OK i will try to explain it.
Killing Partridge (everyone's favorite until season 6) at the first episode before giving away more clues about Red John and not clearly allowing us to see his death ensured that none can be 100% sure about who Red John is. Every theory about Partridge has a big question: "But. what if Partridge is really dead?" and every theory about every other suspect has another big question: "What if Partridge is not really dead?".
By doing this Bruno really ensured that none will be 100% sure about Red John before his actual reveal and he really succeeded. With the blurry death of Brett Partridge everyone asks himself either one of the 2 questions above after completing his thought about a suspect, none is sure.
My Opinion? Partridge is really dead. Cmon! Partridge was the obvious choice even without the list, he was there in every Red John murder, he has a well thought name that they got from one of William Blake's paintings that really makes his fans to be sure, as they think "cmon it cant be a coincidence". Partridge is really the obvious, he fits Red John and you dont need to see his name in the list to suspect him.
For me Red John is Thomas McAlister. He was there since the very begging and he was a safe choice because none could suspect him before they see his name on the list. We have no clues about him and they really don't wanna make us think its him, in contrast to Partridge in which every clue leads to him even the voice (major clue) but i think its a misdirection on purpose.
OK if you wanna see how you can eliminate every other suspect except McAlister and Ray Haffner check this video I made and has some pretty good responses.
http://www.youtube.com/watch?v=ohIxFnOnRCk
Watch my explanation about Red John's voice here, and be aware that when Red John talks he either wears a mask or we cant see his face so check this out.
http://www.youtube.com/watch?v=_AI-RpwT2M8
yeah explained with Bane mask from Batman but its a pretty good way to explain the voice, because the actual Red John would never giveaway his voice ;)
Uh and check this photo:
http://images.buddytv.com/btv_2_800033859_1_434_593_0_/xander-berkeley-in--.jpg