You can be a minimalist in a temperate climate and carry little more than a rain jacket and an extra jersey. It's not impossible to wash what you're wearing during the day at a public restroom or hidden natural setting, put it on damp and wear it dry. If weather doesn't allow that, it's okay to skip a day.

If you're camping add what's needed for expected temperatures

For those cold and/or rainy days, my kit also includes rain trousers, light nylon trekking trousers, hat and gloves, wool socks, clear goggles.

I've taken to wearing a long sleeved nylon trekking shirt on tour for sun and bug protection, buttoned up for warmth or worn open for cooling. Easy to wash, quick to dry. I wear it over a wool jersey for extra warmth.