As title, I don't believe pretty much any of our devices implement comparator outputs, at all. Where they probably all could.

• Basic inventories should show total filled / total capacity
• Fluid inventories, crucible, barrel, etc. should show fluid inventory.

In addition, we could consider adding some limited redstone control to devices, where it makes sense that automation exists (it's a stretch but hey):

• Dispenser + Flint and Steel interact with TFC devices, i.e. lighting them.

Another thing to consider: it might be worth while, developing some sort of in-dev test against a typical pipe based automation mod, to verify our containers all interact in expected ways (we can do item based tests with hoppers, but that also doesn't fully compare since hoppers are vanilla and mods will interact in different ways). Stuff like verifying the sidedness of our interactions. (Also, sync issues, because I uncovered one just by implementing barrel + bucket + dispenser interactions)