Tall Personal Shopping: Tall, Slim & Athletic

My son is 18 and he’s 6’4 but only 175. He has a 32”waist but feels like pants that are 36” inseam are “too short.” We are looking for pants that are 32×38”. He is an athlete and likes slim fit. He is also looking for shorts that will cover his knees and shirts/ sweatshirts that are long (and have long arms) without being for someone twice his weight. Any suggestions for a young, athletic kid who is tall but not big? Thanks.  Here is a photo of him.  He plays football, now has dreds and doesn’t want “dorky old man clothes.”  He likes the Hundreds and Crooks and Castles and similar brands.  He prefers slim fit jeans.