(Yay! :D )

Here's my take on 3) (alternatives are welcome):

I can see 3 types of behavior people could want for LPE width: - absolute width: most useful for thin lines. Ex: 2 px. - % of original (%): big clipboard items. Chances are, when you copy an object you've just made for LPE, you want the object width to be more or less retained. - proportional resize: actually, isn't this what "bend path" more or less does? The object isn't stretched, it's just resized and bent.

At first I was wondering how to call the last option in just two letters, but then I realized that it's best to make that a repeat option:

http://img150.imageshack.us/img150/2599/lpekz5.png

So, apart from the above, you have the following for units drop-down:

% -- px mm etc.

By the way, there should be an option for the resulting object to take on the color/fill properties of the original object instead of the current line properties. This in particular could be set as default for clipboard items: - if you copy a green leaf, you probably want it to stay green - also, if in the future you can copy complex objects with different fills and strokes for LPE, that'd allow you to retain those multiple settings

Also, is it possible to implement a "skeleton" mode where all LPEs are disabled and only the skeletons are visible? The reasoning is simple: LPEs can consume a vast amount of memory. A skeleton mode would serve very much the same purpose here as the Outline mode (indeed, the outline mode itself could be made to only show skeletons and not rendered effects).