What we know is mage as secondary will probably provide fire/ice/wind/teleportation augment schools, cleric will provide death/?/?/life augment schools. What other class augment schools you want to see or predict seing and how they might improve primary class skills?
I would love to provide you all with more details and information. However, these things are not finalized so anything I could say to you would be subject to change.
With that said, we hope to have updates for you on classes and augments very soon. It's something our teams are working diligently on ^_^
Like OP suggested, I would love to see you all come up with additional ideas for augments for secondary classes! What can you imagine, I wonder? 🤔💭