There's some great new art in this mod that you could use.
https://steamhost.cn/steamcommunity_com/sharedfiles/filedetails/?id=682190594

Ooh, do they indeed look great. Thank you for your suggestion, I'll make sure to take a close look when my pc is fixed

I'd love if you could add either a species trait or civic for mages. Maybe tie it into psionics?

That's certainly a very neat idea, however I've been busy recently so I might not learn and implement it for now. you may consider using Trait diversity in the mean time.

You can use aerobatics, army traditions, precocious and/or other psionic related traits.

Also, I believe that there's the "war enginners" civic on this mod but that may be another mod that I used, hope that this helps