I always asked myself why SwiftKey keyboard doesn't show up and hide in an elegant way and now even more when we have Nougat/Oreo with beautiful screen transitions, material design, etc.
Isn't possible to elaborate a sliding effect just like iPhone and even the Samsung default keyboard?
After testing other keyboards in the last days, I just realized that, although this is something minor, it's the type of thing that makes usability more pleasant, more fluid, smooth. So much better than just appearing and disappearing suddenly.
Don't know if it's something thought to reproduce in lower end phones, but could be something available in settings at least.