Cases that actually protect without adding bulk?

Has anyone found a case design that protects the device without doubling the size or blocking access to charging and refill points?

I am less interested in decorative cases and more interested in something that prevents scratches and accidental button presses without making normal use annoying.

That is exactly how I evaluate them. Access to controls and ports, retention, added bulk, and whether the case traps residue all matter more than the number of extras in the package.

I prefer a thin sleeve with a slightly raised edge around the control area. Full hard shells always seem to add more bulk than I want.

A raised control edge is a good idea. That solves the main reason I want a case in the first place.