Sanderson for 10 Year Olds

My son loves listening to Sanderson books on car trips, but we're running out of books appropriate for his age.

So far, we've done:

  • Skyward Series (all but the last one, which doesn't seem appropriate for his age)
  • Skyward Flight
  • Alcatraz Series
  • The Rithmatist
  • Tress and The Emerald Sea

I've personally read the original Mistborn series, the Reckoners series, and the Stormlight Archive, but I don't think those would be appropriate for his age yet. A lot of the newer stuff I haven't read yet, and others I read so long ago I don't remember what is in them.

What else might he be ready for?

Or, other authors we should investigate?

Thanks!