I have a suggestion concerning the key modifiers associated with actions: It would be great if the sequence how these modifiers are pressed wouldn't matter.
Before I explain what I mean let me introduce some notation: <key>+ means <key> is held down <key>- means <key> is released
Example 1) if an action has the modifiers <ctrl> and <shift> then the action is not triggered when the modifiers are pressed in the sequence <ctrl>+ <shift>+ <shift>- <ctrl>-
Example 2) if an action has the modifiers <ctrl> and <alt> then the action is not triggered when the modifiers are pressed in the sequence <ctrl>+ <alt>+ <alt>- <ctrl>-
Example 3) if an action has the modifiers <alt> and <shift> then the action is not triggered when the modifiers are pressed in the sequence <alt>+ <shift>+ <shift>- <alt>-