The Atlas Executive Holdall from Waterfield is an excellent large-ish capacity shoulder bag designed to help you shift seamlessly from tech gear to gym gear.
Other Bags to Check Out:
The GR2 from GoRuck will last your entire life, features a segmented main compartment, is extensible with pouches and accessories and boasts a very rugged, handsome look.
The Monolith Daypack from Heimplanet is a 22L carry-all daypack made from great materials with a solid aesthetic and plenty of attachments for accessories.
DSPTCH hand-makes bags here in the USA and the Travel Pack is a great example of the kind of extremely durable designs they put together.
The Guide Pack from Tom Bihn is a bag geek's boner pill. It's classic design and exceedingly excellent manufacturing make it more like an heirloom than a bag. But this bag also performs great as a travel bag!
A truly lightweight and sturdy bag that can carry literally everything you can throw at it AND make the load as comfortable as possible to carry.