Hello

I'm looking for a simpler alternative to the dry bag + (backpack | Eastpak travel bag) that I currently use to commute or tour.
It's especially a pain when touring because it takes several minutes to force the travel bag inside the dry bag when it's a bit full.

Ideally, it should be...

• as light as possible while being 100% waterproof even if riding for hours under heavy rain
• have some inner pockets so that my stuff isn't all mixed together. An especially useful feature would be a separate pocket to stuff wet gloves, etc.
• have a shoulder belt so I can carry it on my back as an alternative to securing it on a front/rear-rack.

Are there good brands I should check?

Thank you.