I think it'd be pretty simple. Change his SR to spell immunity, and make it proper "No, not even Conjuration (creation), fuck you wizards" - let it be overcome by a successful rank check. Allow him to define gravity subjectively within 1 mile per rank - he is a primal manifestation of existence, after all. Hood builds should be sufficiently fucked with when they fall away from him, although I'll admit I haven't studied them very well. Give him an appropriately high Int score, coupled with a special ability that goes something like this:
"Blank Slate (Ex): Although its Intelligence score might indicate otherwise, Azathoth is actually quite stupid. It is incapable of logical reasoning or foresight, and the closest thing it has to a mind is a roiling chaos of ideas, ever clashing. Nevertheless, Azathoth knows virtually everything about the Universe; it is simply incapable of reasoning with that knowledge. At the same time, Azathoth has every thought it is possible to have, and several that it isn't; but these are unconnected and fleeting. While it reacts to its immediate situation with all the apparent tactical cunning a creature of its Intelligence score might display, this is instinctive and simply a manifestation of the myriad of thoughts that compose this deity. Thus, it will never plan in advance a cunning strategy to defeat a foe or defend itself, nor will it consider the ramifications of any action for longer than 1 minute into the future, nor does it seem to remember events more than 1 minute into the past. For the purposes of any check, roll, or other mechanical purpose other than a Knowledge check or adjudicating ability damage, drain, or penalties (assuming one is somehow applied to it despite its normal immunities), Azathoth has Intelligence 2. Furthermore, because it cannot realistically be said to have a mind, as the term is typically understood, it is treated as Mindless whenever it would be beneficial to it."