Originally posted by Uriel005
he even explains it outright to Donna as well as she's burning out just from being a timelord. The process of moving from childhood to adulthood is looking into the untempered schism... and that is a much bigger rip than the little one sitting at the heart of the tardis which allows the timelords to experience well... everything kinda what everyone thought drove the Master mad before it was discovered to be Rassillon dickery. Also what was killing Rose was not just the vortex. It was the entity of the Tardis itself combined with gazing into time itself... Something that had the power to sustain a microcosm in a collapsing universe and keep looping time as it exploded again and again and again is not meant to be in a human head.
In none of the instances you mention is it clear that he can see every potential outcome beforehand. In a couple cases, it's even self-refuting, because he doesn't "see" the one lady killing herself at the end of Waters of Mars. And the schism isn't the same as as the entirety of space-time being inside you at all times. He can perceive time as it unfolds, and see things like fixed points. That's about as far as we can say without getting wildly speculative.
What you're talking about is omniscience, which is silly even by the Doctor's standards.
Lastly, "lol bad writing" doesn't change primary canon by the most influential showrunner in the show's history. I refuse to concede the Eccelston point.