A 1% chance per sift to get coal is ridiculously low considering you:
-need it to power the furnaces that smelt iron, copper, and pure sand
-need it to make rocket fuel to power a rocket
-need it to do coal liquefaction which is the only way to get oil products on Arig
-need it to make plastic to make the press as well as rocket parts (advanced circuits and low density structures)
Combine that with no way to intentionally destroy excess resources ala Fulgora's recycler until after you already make the planets science.
Coal is just too rare for how much you actually need. A higher chance along with intentional recipes to produce oil products (if coal liquefaction isn't the intended way) and a way to void excess resources (throw it into the sand!) would make the planet progression much smoother as you aren't stuck waiting for enough coal to make plastic or on any specific resource while the rest clog up.
