There’s a couple things from the Revenge of the Sith Novelization that really should be in the film, as they seem important to understanding Anakin’s motivations. (Really the whole film probably should’ve used a condensed version of the novel as its starting point, but I digress)

First, is a minor mission to a dying star, which utterly shocked Anakin to the core, and ate at him forever since then. What would he do without Obi-Wan or Padme? What would they do without him?

The second one is the entire reason he got so angry over not being granted the title of Master. Basically, he was trying to see if there was something regarding using the Force to prolong life. However, that part of the Jedi archives was locked off to the Jedi Masters, and his situation wasn’t really one he could talk to them about. So Palpatine appointing him to be his representative was seen to be his was into the title of Master, and thus into the archives. Except Mace Windu said that Anakin merely had a seat, not the title.

Also, Make Mace Windu into more of an obvious antagonist for the rest of the films. He’d represent the most strict and repressive interpretations of the Jedi ways, a clearer sign of how far the Jedi had fallen by the era of the Prequels.