I'm learning Blender and Python at the same time (coming from a Maya/MEL background) and have created my own alternate Octane UI panel for the Node Editor:

I've been using Octane Render with Blender a lot lately and I find this to be a bit more compact. In future I hope to add some 'smart' features like, when creating a MixShader or MixTexture with other nodes selected it will hook them up to the mix automatically, etc. For now though it's just an alternate button layout. You can re-order the buttons quite easily by editing lists at the top of the script.
I'd like to stress that:
- I'm a Python noob, so you may well read the script and laugh/cringe at the horrible methods I may have used.
I'll improve it as I learn!
- This requires the official Otoy Blender plugin and leverages what they have already implemented.
- It's not perfect! But it shouldn't cause any problems.
- Currently when switching between the Object and World modes of the Texture node tree, the UI doesn't seem to get updated. You have to switch around between Shader and Texture mode to get it to re-sync. I'm not sure why this is.
- When you press a button and create a node, it is created at the 0,0 coordinate of the Node Editor.