I agree that QAvimator feels limiting. That may change eventually.
For a free Blender solution, I recommend the following download from Domino's blog:
Go to http://www.dominodesigns.info/
On the right side of the site is a list of links that says "Forums", "Primstar", "Download", "Manual", "Avatar", etc.
Click the link that says "Avatar"
This will download a .blend file ("avatar.blend") that contains a nice basic setup of the Second Life avatar in Blender. I think it may be the precursor to Avastar, so it's not as feature-rich as Avastar itself. However, it is decent and I have used it to make a few animations and poses.