It depends on what you are mixing, if your mix contains primarily recorded samples, then compression plays a big role. But, if you have designed the sounds electronically, compression isn't going to do a lot to take your mixes to next level and you should revisit your sound design to take it to next level, but again, multi-band compression as a creative tool can be used extensively in sounds that are created electronically.
Natural sounds generally have big dynamic range, and that's their charm, which separates their "feel" and fidelity from electronic sounds, however purely natural sound may feel weak in a mix, and there you use a compressor to reduce the dynamic range and make them more powerful without altering their character.