Correct.
For the rest of your question... I didn't really understand, but you'll probably want SSR Tsuku AND SSR Artemis just because they're SSRs, and SSRs are good for you. Herc can cover the rest of the debuff cap for you if you want. If this is a Miracle Ticket question, then come back and ask once Miracle Ticket is actually out. There's no real reason to plan anything until that happens.