I happened to catch an interview with Keegan-Michael Key on one of today's morning/midday talk shows (Good Day America or something like that) and they covered The Lion King a bit. Nothing huge or particularly meaty was revealed -- they didn't even mention his role in the movie -- but he said he was honored to be a part of the cast and he's loved The Lion King since it first came out. The most interesting thing he said was that when he first learned of the remake he wasn't sure how they could've improved on the story, but apparently he's since been blown away by the project on more than just a visual level. Granted, he's doing a low-key promotion (it was on ABC, which is Disney-owned of course) but I still like to think there's some real merit to what he's saying.
Edit -- Just found the interview in question: https://youtu.be/PTTbXv5tK5k?t=101