LeechCraft

Could you please provide more shortcuts to customize if you want them to? I doubt I'll guess everything correctly.

Actually, these are the most wanted.

I can also suggest "Quit" (no F10, thank you very much, NC is dead) and "Switch to next/previous tab" (that'd at least enable users to add another shortcuts.

Let me vote for "Switch to next/previous tab" hotkeys too. Moreover need them work globally.

I doubt it's a good idea to make them global. You need to have different shortcut for global switching, because else typical Ctrl+Pg{Up,Down} would be broken in other apps, and the mechanism for setting global shortcuts in Qt is somewhat complicated. I would rather expose something like D-Bus interface for such things and offer a configurator for global shortcuts that's able to invoke commands.

Or finally implement some scripting language.

Good idea for a separate "via DBUS" configurator.. Seems the one KDE provides in "systemsettings" will suit.