This is a Sunday brunch with the guys or family outfit! I feel like you don't have to wear dress pant to wear a blazer with a dress shirt. Just throw on some plain, simple jeans and add on that beige blazer with a neutral color dress shirt.
A smart casual combination of a light blue check dress shirt and beige chinos can maintain its relevance in many different circumstances. Tap into some David Gandy dapperness and complete your look with dark brown leather loafers.