It's not quite as bad as it looks, but you are correct: there is a lot of work to go!
Almost all of the weird stuff going on in these pictures is a result of transitioning the existing code from a completely ad hoc system of measurement (with units loosely based on the size of Synthesia's notation texture) and staffs that were always a fixed distance apart to a much more principled system of measurement (with units in "staff spaces", which are used by musical fonts, engraving experts, and all of the literature) and staffs that have a variable baseline. Now that the dust from that transition is starting to settle, it's just a matter of reconnecting all the bits, replacing the old, made-up magic numbers
in the code with the recommended values
from the font we're using and making sure everything looks the way it used to.
That will be the first Synthesia 11 dev preview. It's not an especially exciting one, but it'll be nice to get it in your hands because it's got a number of other fixes and improvements. I don't like to wait too long between previews.