When you have bought the TS-E 24mm L II - which I think you should - but before you get broke on other Canon gear,
You should get a Lumix DMC FT4.
This is a real pocket-camera - no protruding lens or never-ready-lens-cap; you forget it's in your pocket.
But you can skin-dive to twelve meters if you want.
I have used my FT1 for nearly four years and thousands of shots. It has survived bumps and scratches.
Hand-held film and stills running/jogging, x/c ski and bike racing, mountain hiking, kayak paddling,
swimming and diving with grandchildren. UV filming trout on the hook. You will certainly find out more ways.