9.
Also, I'm not sure does Snatch work in raids...? Since most proper raid drops are Plat drops, which might not be affected by Snatch. Dunno.You have a few days to play the game and decide do you want to drop money on it. If yes, Miracle tickets would get you far even in Light. Second one would get you SSR Tsukuyomi who makes Light plenty good. On the first you'd pick one of the current SSR, probably Raphael. But again, the first Miracle ticket will expire in a few days. If you're not sure if you're going to keep playing or not, then it's probably better to pass on the first one.
As for Accessory quests, you need to get your basics sorted out first. That means months of hard work on events.With that, you might as well not be in a Union, really. At your level, your best bet is to find a strong Union and just enjoy the free loot. But... I don't know if you'll find any Unions who'd take you. Notice that you'll need to leave BEFORE the event starts, as you can join Unions during Union event but you cannot leave them.
Union events are miserable for those who are not part of a strong Union, sadly.You've spent ~100k on Gems gacha today, come back after reset.