Advice needed. Is S2 worth it?

I'll describe my situation to the best of my ability so any help is appreciated!

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Does anyone know what will happen to the collab banner after 3.4?

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I got my first Lucy in around 140 pulls (70 Verina, 70 Lucy) and now did another 10-pull using the free pulls from the login event and got Lingyang at 6 pity.

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I'm debating whether I should go for Lucy's S2 (I already have S1R1). Should I leave my guarantee there or is S2 worth it? What does it even do and how much of an upgrade is it compared to S1?

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Would love some advice here pls.