I'd add hyphenation to the Text items. And the ability to specify in points instead of pixels at least the size of the type.
Which points? There are several definitions of the unit "point". (Well, I imagine you could just go with what most do.)
The point that probably every graphic designer expects: the postscript point, which has been for years the standard for DTP (1/72 inches). I know I can get the desired size with simple math, but it's annoying and error prone when there are several text elements in the document.
Also, this would require Inkscape to write out SVGs which have a clearly defined absolute size, which we still don't if I'm not mistaken.
My reasoning is simple: Inkscape uses 90 dpi as default resolution to make the translation from pixels to real units (for instance, when I use inches as default units and I want a square of 1 by 1 inches, a square of 90x90px is drawn). If I need type in points, I can simply multiply the desired size in points by 1.25 I get the equivalent in pixels for that resolution. What about putting a unit selector in the type dialog allowing to choose points instead of pixels? When pt is selected, the real size used would be the entered value multiplied by 1.25.
(There's another GSoC project for you.)
Unfortunately I'm not eligible at all. I was just adding some points that are (afaik) also SVG compliance issues