The sequencer is probably the most powerful item in the game as it is now. Here are a couple of suggestions to make it a bit less power full to make the need for the other items (belt conveyer, voxel materializer/dematerialize, atomic compressors) higher.
Limit the "Input" field so you can only pick up stuff from it, not be able to put in stuff directly there. This way you will need to use Atomic Compressors, Voxel Materializers and conveyer belts to feed the Sequencer.
Make the "Sequence" field not store actual voxels. This is to prevent it from being used as a high capacity storage device. Explanation: If you drop 1 Coal in to one "sequence" slot you don't decrease the players inventory, and if you pull one Coal from a "sequence" slot you don't increase the players inventory. After all, it's just the blueprint for what to sequence out, not actual material.