This always kills it for me, I adore Finn so much and lately they've done such a good job with him that I'm even okay with the shit arc that happened to him in season 5 and 6 because he climbed out of it and it feels very earned, but they have never succeeded with his character design.
It's a pretty important part, and it would have been wonderful to see it age alongside his personality and voice, but it never happened. At most they make him taller sometimes but aside from that he's identical looking to at the start of the show (well they draw the ears of his hat differently at times but that's about it).
The worst part is that they're probably gonna do a timeskip and show Finn with that Xbox Heug Finn design that's been in the series a few times, but that'll be ridiculous because we're going from short, chubby Finn with noodle limbs to jacked as fuck with glorious muscles and shit, and I think the design looks shitty anyway.
This Finn design isn't perfect (that ponytail is so dumb) but it serves as a great example of an interesting direction they could take with Finn's design which I know the show won't do anything like and it kills me. Finn's awesome! It would be nice if he looked awesome too, you know?