As a designer (and I think every designer out there will agree, specially type designers) I'm against those faux styles. They're never good, and they can lead the unaware designer to think that certain typeface has a bold or italic variant. If we want free software to become a viable option for professionals and serious users, we have to avoid this kind of things. They make our program look cheap, amateurish.
I'd be happier to see a specialized tool to create offsets, like the existing one, but optimized for type, so we can easily create different weights keeping the features of the typeface (of course, it's probably impossible to create a bulletproof tool for that and some manual tweaking is needed, but as a starting point it would be very useful).
And that would be only for weights and to avoid current workarounds like using offset or adding outlines to make type bolder. Faux italics shouldn't exist at all. Slanting a font is a crime, italics are never the regular glyphs slanted, it's a completely different set of characters, designed from scratch.
Gez