Once VIC-III bitplanes are fixed, there may be one final round of VIC-IV fiddling and some residual bug-fixing, but after that we expect the spec to be more or less settled.
I did discover a funny little quirk with the screen background colour when behind text, however. We currently latch and buffer the border colour for the whole row of pixels in the character, instead of reading it afresh every video clock tick. Not sure yet whether to call this a bug or a feature...