Many operators have modal options available to the user but many of these are not displayed in any way and remain totally hidden. In many cases these options are only found accidentally or by reading the documentation (assuming it's up to date).
Add modal options to the 3D view header for each operator. The Knife tool can be used as a good example. The header should include option names, hotkeys, and status in the case of toggles (such as cut through: ON/OFF).