They should put more effort into streamlining the API again, and I'm not sure why we don't have a single state vector yet, neither why samplers are not solely shader side for example.
It would also be nice to be able to generate and submit a command buffer sequence easily. (Create it once, resubmit it as many times as you want, sorta like a copy/paste operation.)
How many ways do we need to specify a typed multi-dimensional array ?
BufferData, BufferStorage, TextureImage*, TexStorage*... That's way too many...
The API is at last giving us access to hardware features that have been available for years now, but the API isn't making the jump I'd like to see and change once and for all into OpenGL Lean & Mean, a promise from 2002 for OpenGL 2.0... (Long before 3.0/Long Peaks)