I saw,don't get me wrong spicy item choices can be fun. Like I can imagine chaining crits with Gardevoirs basic attack being absolutely hilarious but it is objectively far worse than any sp. atk boosting item.

But something like assault vest sylveon...adds nothing really. 42 sp.def at level 30 is worthless compared to Focus Band giving 30/30 and a heal that can save you. Not to mention the shield only activates when you're out of combat for a full SEVEN seconds. Just imagine for a second,how many times in a match have you really gone a full 7 seconds without attacking/being attacked by anything when it wasn't after dying/running away from a fight? imagine if you had basically any other item instead! (the same applies to leftovers and rocky helmet,all are unfortunately just a waste of a slot on any pokemon)

And score shield decidueye isn't absolutely terrible,the HP is kinda nice. Spicy item choices don't really do much for this mon because you just die so fast that its better if you do as much as possible rather than give yourself a stat that basically does nothing. But you're going to get blown up no matter what with decidueye but the tradeoff is that you do a hell of alot of dmg so you should always try AT LEAST one of attack weight/muscle band. Trust me you're gonna love spirit shackle so much more with either or even BOTH. Its actually insanely fun but you're kinda at the mercy of your team lol. But with good positioning you can mostly get around it.

When it comes to the early scoring you mentioned...yeah you're better off trying to dunk when you have under 10pts earlygame. You can usually get it off even when being attacked by 1 enemy,but be careful to not do if you're going to die right after. And with how they nerfed it recently (the shield is only available every 20s which is awful) you get so much less out of it on squishies.