WebGL is indeed low-level. That's not a problem if you already have the tools and functions in place to manage your scene data (meshes, materials, shaders, rendering optimizations, and so forth). It just means you need to be familiar with the graphics pipeline, how it works, how best to optimize it and what the subtle bugs and workarounds are from one video card driver to the next.
In terms of frameworks, I'm afraid I'm a bit biased, since I'm authoring one. :)
I've been putting a lot of effort into Jax ( http://blog.jaxgl.com/what-is-jax/ ) to make it as powerful, simple and flexible a framework as possible. It borrows a lot of its key concepts from Ruby on Rails, using Ruby in the background to generate and automate as much as possible. This lets the developer (you) get down to business right away, instead of fiddling with implementation details. The end result is 100% HTML and JavaScript, so there's no need to fret over compatibility. If you're up for trying something new, give Jax a shot. The link above talks more about the details, and I've recently put a "Quick-Start" page online ( http://jaxgl.com ) if you'd just like to hurry up and render something!
