I bought a pair of Shimano MT33 shoes after I found an ancient set of SPD pedals. This was simply revelatory - the difference as as significant as going from flat pedals to clips. Pops in easy (well, not always on these old single-sided pedals), pops out instantly.

The cleat is recessed enough so it doesn't scrape on anything other than rocky ground, the sole is stiff enough for decent distances and the upper hugs the foot so it doesn't shift around. It even has a small elastic bit to keep your laces in (crucial, as I discovered this week when another shoe's laces tangled on the pedal spindle at a high cadence). However, they're "walkable" - they're shaped so your motions are still natural, but it's not the most comfortable thing to do over longer distances, nor is the thread grippy on wet surfaces.

However, my pedal wrench has become my best friend. I usually stick with clipless if I'm going to work (extra shoes in my bag - as a waiter, I walk a lot and can't afford to use uncomfortable shoes) or going about my daily business, but I'll swap them out for my old clips if I'm going out, or if my schedule is so packed my bag can't hold the extra work-shoes and cycle in those.