Envelope scripts ?

Does anyone have some custom actions or scripts that will let me create each of these with an assignable shortcut key please ? You can assume there is a time selection if that helps. Thanks in advance !

The last one: (from post #4, edit: the lowering amount is variable) Needs Python installed though, not sure if it's worth the hassle if you haven't, maybe there's an alternative way.

thanks but it's not worth installing python for :-) We could really use some very basic shape drawing actions and not the freehand drawing tool that machine guns envelope points on the screen like a popcorn machine.