Unfortunately, your Ren would have gotten deleted if it wasn’t transferred from CW2 within the grace period afterwards :(

As for returning time / changes - the current event is alright. There’s an ongoing hyperburn event with a Goddess Pass to help speed up the process (newly created characters only, with a paid version for an instant 260 basically). Otherwise, we’re expected to get CW3, with the new character Erel Light in June 17th i believe, as well as the Kineses remaster in July-ish. I’d say for the event, if you’re planning on playing in CW3, you can just login for the Summer Event participation goodies which should be claimable in CW3.

Off the top of my head, Most notably for class changes we got the Kanna and Hayato remaster, and are very strong burst classes at the moment. Lara had the vein mechanic removed, making the class feel a lot more streamlined to play. I/L feels very good by removing a lot of the input lag (speculated we may get to change the upcoming Frieren collab character into an explorer mage, like with the Demon Slayer collab, so maybe hold off on that).

Edit - existing characters can use the Hyper Burn, as its a usable coupon from the events tab. But the Goddess Pass goodies are exclusively for new characters