the compressor should be a big block that things should walk through.If mobs walk through it,it would turn into a cube which u can carry around and spawn it where u want.Like with pigs for example:you can compress for traveling purposes if u run out of food just release the pig and kill it for food.Also there could be different types of compressors for different jobs examples: like u said a diamond making,a machine that can compress different types of food together,or a robo compress that protects u and moves around,and my last example is a trans porter that when the thing is compressed it is transported to the nearest chest. That are some of my ideas people can use. Message me if u like my idea.