Howdy I have been also using Inkscape for a lot of icons lately and here's why I keep using a duplicate view instead of icon preview even if it takes a lot more screen estate and makes it only usable on an LCD:
* I need real time preview. While working on a zoomed-in canvas (finer curve control, pixel positioning at the current view level, etc.) I can check the perfect pixel positioning in the 1:1 view. * A single icon will not work for 16x16, 24x24, 32x32 and 48x48 as the preview makes me believe I can somehow tweak it to. I only want to pixel position for a single target resolution[1]. * Define some zoom ratio (no filtering) so the target raster is clearly visible even on a CRT. The current fixed way kinda works too, although I would prefer making it a bit bigger.
Maybe my needs are drastically different to those of your artist subject :), but I'd really fancy an icon preview window/dock that would be updated in real time and show the whole canvas (or optionally select a group id to render for your inkscape icon canvas case).
cheers
[1] - http://jimmac.musichall.cz/weblog.php/Artwork/ScalableIcons.php