>>1720778>>1720805>day packdon't listen to these people. if day packs were useful they wouldn't be found on the backs of a hundred dead hikers every year.
get a larger pack with a waist strap, like in your pic or bigger. a big main compartment is a must, plus durable compression straps but above all make sure you can adjust it to be comfortable. there's nothing worse than having to carry all of you're gear in an unbalanced pack the makes your muscles burn with pain.
the reason a day pack is a no go is simple; you don't know how long you'll be out there. sure, you can plan to be out for a day, but a lot can happen in a day. thousands of hiking horror stories have started with a day hike. the hiker packed enough food and water to live comfortably for a day, and a week later search and rescue find an empty pack strapped to a rotting corpse. don't be that guy/girl, get something you can really stuff with essentials that will last long enough for someone to realise you're not where you're supposed to be.
it's not extra weight, it's extra life.