DO NOT BUY level 4 magatama, if anything buy lv2 magatama.
If you buy 3xlv2 magatamas It's at the same price as buying 1xlv4, but untill you have level 3 magatamas on everyone, it's just not worth it. you lose so much on merging them.
I'd honestly suggest starting with refining runes until you have all equipment at level 4 on your main at least. That initiative is going to win your some matches (or lose if you don't have it lel).
After that maybe go for moods (while it's still 2 moods scrolls a pop, when it's 10... it's probably not worth it anymore)