I've just started playing on subeta again after a 5+ years long hiatus, and I'm reacquainting myself with the site. I'd love some suggestions or tips from current users! Any essential new dailies or new features I might have missed? What are all the cool kids doing these days?

This guide is fairly new and great for any questions you might have. This guide will help you with dailies and such.

other than that, just explore and see what is new. if you have any specific questions, I can try to answer those :)

The places linked are great. Just thought I'd mention one of the better new dailies, the Bathhouse. Prizes ramp up if you go daily for 30 days in a row. Includes several days where you can pick up a bit of CSC and one day where you get a referral point (among other useful prizes).

Subeta also has a fansite Subetalodge and a wikia, each with their own random bits of information.