I believe they're quite aware of the skillbar issue and are working on a solution, and reworking a lot of the UI in general. I think it'd be nice to be able to put a permanent set up 10-15 skills as an optional sidebar, probably smaller than the one on the bottom, and then maybe expand the bottom one to contain 15 skills or so. That way you could have 25-30 skills available at all times, which is plenty for lots of characters and for most of early game, and then you'd probably only need one or two extra skill bars filled out at the bottom.
Or maybe you could have a button to expand your skillbars to show all your abilities at once, stretching to the right along the bottom and then going vertically on the right for a max of 40-50 skills, and it'd optionally auto-expand when you enter combat. Most people are willing to sacrifice a bit of screen real-estate for convenience.