Look at my reasoning for staying on. We get to see Ock crash and burn in the most spectacular way possible before Peter shows up to take back his life!
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Yeah, plus we now that when Pete does return all the bridges he had built will be burnt and no ally will trust him completely again, most likely thinking that he's back to his jokey personality because he failed spectacularly with 'his' attempts at creating his own super team, army, etc. The only people who would still trust him even remotely would be the Fantastic Four, Carlie Cooper, and Anna-Marie. And the last one might not last for long because Peter's personality is radically different from SpOck's, the guy she had been dating.