In the picture you posted, there were other issues:
- in the limit case, the (italics) f overlaps the a
- in the limit case again, the arrow is 'too high' compared to the x and a
- also in the limit case, the x and a stick too far out
- in the expression palette, in the piecewise case, the < is not baseline-aligned with the x and a
- same case as above - the < is from a different font/size than the <=
- the baseline alignments in f := a -> b are screwed up in many different ways
Someone should seriously translate (by hand!) all of these into (trivial!) LaTeX and look at the resulting output to see how is should actually look, and fix all of these bugs. I am sure there are more, but the ones above are the really obvious ones.