His original design is classic but aged same as the early Mario depictions. His modern design is still too rooted in the era in which they tried to evoke an "Extreme, Teen, Anime" vibe like Ultimate Spider-man for instance. It got better after Unleashed and it's the best design yet but I really felt the opportunity with Sonic Boom to actually create a new iconic look, whether that would be like Paper Mario or the Cartoon Network version of Teen Titans, but they missed because they had conservative people in the management at Sonic Team that said "Oh no, it doesn't look like the current designs at all, this is bad!"