I do something similar to the method you mention for #3, but there is another scenario it doesn't work that you might want to be aware of.

Let's say the correct path is north then west. If you come to room #1, drop a marker and go north, and in the next room go north again and wind up in room #1, then you start going other directions in room #1, you'll never find the exit since you already went north in room #1 the first time.

So ideally you need some way to exhaust every possible sequence of each direction, not just one room off, or try to remember which directions you're trying.

Hutto, the Sleepy