I think the #1 reflects the "draw freely" concept better, as it is a bit playful and not too formal. I like the shapes of #4 better but it's too formal. I can hardly imagine somebody drawing such shapes freely. #3 is really poorly drawn. It's free writing indeed, but its so poorly executed that it would make the brand look lame, amateurish.

So my vote goes to #1.

Btw, please reconsider the size relationship. In these samples Inkscape becomes a second hierarchy, like a news kicker. Inkscape should be always the most prominent line, with the tagline in a second place.

Gez.