To be frank, I have no issue with Devon's new sprite, though he does look kind of young. Perhaps mod it a little to show that he is older than his students, maybe? Other than that it's perfect. Kudos! :)
But that's it, right? He happens to not be much older than them and has been teaching for only 2 years, if I recall correctly. Apart from this I think so as well.
I see, thank you for the key information. However, 29 years is not significantly older, so some people might look like their younger selves even at this point. Although Devon does appear younger than before.
