Monday 22 June - 10:08:27 PM
Don't really know how to communicate with the developer group(s) on these user boards, which I do glance at now and then, and being in the midst of 'the important work' I must learn more about that a little later. 
Though a new and often searching user, I do already very (very) much appreciate this Inkscape thing, and want to assist in the developments to whatever extent I might. 

Two things so far: Loaded in the Trunk version on the 20th to see what that was like, and then put the stable version back in today. 
(Mint 17 operating system) 
Changed back for just the one reason really, the Trunk no longer contained 'delete all guides' in the edit menu. I use the 'objects to guides' quite a bit to guestimate reasonable seeming perspectives, particularly when the piece is simple enough not to bother with a paper drawing or a Sketchup model first. (Those sudden nests of guide lines, only loosely related to any real vanishing points, sew confusion onto next uses unless I can keep dismissing them wholesale.)
... That 3D emulator-or-possibly-actual-tool, that is there among the available functions; I've had to tag that one for some future  study session.

Speaking of the guides, though the labelling and information options are pretty darned useful for getting precise with, it would also be good to be able to push guides around their rotation points by eye, as well as with the deg. entry. (Even though that protractor tool is a completely fine little gem.) ...Wait, let me try something here....OH MY GOD, control shift gets little rotation arrows showing and going with stepwise changes, and then shift by itself allows for smooth rotation.Inkscape Are The Best!

I also think it would be useful to be able to pin different groups of guides to given layers. - Probably also a feature already available and awaiting discovery eh? 

One last other thing to mention, very minor really, about that Trunk version. A single straight line will not be blurred unless it is manipulated first, though even a very subtle bending was enough to do the trick. As arrow-straight lines are pretty much a wierd and overpowering spice within the 'loosley suggestive' styles of drawing anyway, I found this one by fluke.
And it was late at night, and I was tired, so, I am not really sure... The line vanished and an empty selection box grew around where it had been as I increased the blur number. (drawing effects such as pencil and sketch seemed disabled too, but by then I had made a decision and went to bed.)

Thanks again folks, for this Inkscape thing. It's a starred line-item on my volluntary payments wishlist.