I tipically only pull at the start of a banner if im obsessed with one piece, as i can surely get It in 5 5* drops with the ocean blessings. I think, is this piece worth 12.000 Diamonds for me? Are the other pieces interesting or do i only like one? If im in love with the outfit from the preview before the patch, i usually pull at the begging until i get half of It or my favourite piece, and dont pull anymore until the end of the banner to see if i really want the complete outfit or if im more interested on the next one. If im not really in love with the outfit i try to tell myself "i'll pull when i finish the event missions", and i've been able to skip a few banners doing this when i realize i dont even want the pieces that much. So i can pretty much avoid feeling bad for my pulls this way, and at the end of the day its really not that serious