It would be great to add alternative fluids to the ore washer, ones that are harder to make, but give you an extra bonus dust.
Also, one thing games use these days is random bonuses because a random output is more exciting than the same thing every time. Maybe if the ore processing machines at rare times gave you a rare bonus dust or tiny/small dust.
This combined with the alternative fluids would be interesting IMO. Run your ore washer with distilled water (or IC2 coolant) and you get an extra small bonus dust of the usual type, but 5% of the time it extracts a tiny bit of uranium, or a fragment of diamond, etc.
To me, it is fun to have choices. Invest in making large amounts of this fluid and get more output vs just using easy to acquire water, save on the investment of time and resources to get the second fluid, but have a little less output in ore processing. Its what makes Tinkers Construct so popular, you have a zillion choices on how to progress. Why not offer alternative paths to process ores?