So with the current event (black eggs), when 10/23 comes and goes, I'm assuming the items will not restock and this event tab will simply disappear (or be replaced by something else)?

If so, I still have quite a number of eggs I need to spend. I have already bought out manyus, ampies, and gifts; what else should I prioritize buying...perhaps all the equipment manyu looking things? (I'm 1 levels from 40, tho I hear forging drains wallets...). That or life crystals. I have about +/- 40k eggs.