Olympias had the draw of being Alexander's mother and Philip's wife which gave her the 'auctoritas' to subvert the 'imperium' of Philip III and Eurydike. This is what the sources say, and it is that 'auctoritas' which gives the first execution squad to baulk despite her aura being dented by her cruelty which is given as the reason for the desertion of the populace to Kassandros, regicide was water off a duck's back so long as the new king was efficient and the killing remained within the Royal Dynasty, no one reacted against Alexander for the executions of Kleopatra and Amyntas Perdikka, for instance. So I would concur with you on that point.
One would have to skew Pausanias' character somewhat to make him a noble tortured soul; his basic complaint is that he was used by the lower classes, snobs tend not to demand our sympathy IMHO. It might actually work as one of those stories where the reader guides the narrative, so at the end of a section there is a choice of actions and that leads to a new strand leading to its own consequences, naturally what appear the right choices have to turn out to be bad - so as Philip do you punish Pausanias, appease him with a promotion or punish Attalos? The historical option leads to the historical outcome, but punishing Pausanias will seem unjust and alienate a faction, similarly if Attalos is punished the political alliance within the kingdom is damaged and Kleopatra might slip something into his next cup of wine
