I would take my Cyclops down deep, but would park it in a place that is safe from any large creatures, and continue to explore with the PRAWN.
Personally, I like to navigate the very deep parts of the game with the PRAWN suit instead. Lastly, the sonar upgrade can aid you in pointing out creatures you can't see. The shield generator uses a significant amount power, so be sure to use it only when needed. You may also want to use a shield generator to temporarily make the Cyclops invulnerable. If a creature is coming at you, you can launch a creature decoy to divert them away from you and allowing you to escape. Be sure to use your cameras to be aware of your surroundings as well. You can engage silent running mode at any speed setting to further reduce noise (by 50% according to the Wiki), but it consumes power at a faster rate. The faster your speed, the louder you are, which means the further creatures can hear you. The different speeds you can select affects the amount of noise you make.
