I think the next Arlo plot should be for ancient plants... ferns, bromeliads, palms, leafy stuff like that. Could give us some cool leafy and plant themed familiars, leaf and fern or unique bark clothing items, and obviously a lush ancient grove for a backdrop with huge towering trees and plants.
OR!
Bugs! Ancient bugs! Exoskeletons and lacy wings and giant insects. Dragonfly swarms and things trapped in amber. Obviously we'd get some ancient insect familiars, but the apparel could really lean into the amber aesthetic or spiky isopod plating, and the background would be so cool to have as a giant oversized leaf litter with insects in the backdrop...









