I use a North Face Surge that I picked up for 80ish on offer a year ago. Pretty much the same usage as you for laptop + accessories and it's pockets and lined/padded internal sleeves are great for small bits/adapters. Main compartment has space for clothes and bulkier stuff. I'd say it's shower proof but would need a proper cover for anything heavier. Have used it for a few holidays also as a carry on and is comfy to wear with good support on the straps. Looks like it's currently on offer at Blacks also.