I find it annoying that we're innovating different ways of doing the exact same thing: switching from completely locked to completely unlocked.

I want near-instant access to a notepad for jotting down thoughts. I want more locking for reading existing notes. Still more for accessing email. I want a strong lock protecting apps related to finances.

The simple lock (just to prevent pocket-dialing) should be like a slider. The intermediate lock could be this drag pattern thing (which is just a friendly version of the Android drag lock). The strong lock could be a coded sequence with buttons that change location.