suits with built in hard plastic or abrasion resistant material on knees and lower legs are a plus for climbing onto rocks, some will have barnacles and growth that can cut like razors.
as was previously mentioned - once you are wet from swimming, and up on your rock - any breeze will chill you fast ( and get dangerous if its truly cold) in a hurry of it is open cell neoprene. Suits with a rubberized or wind-impervious material around the core have been very valuable to me. The alternative is an overlayer of windproof material like a windbreaker or rain jacket- with no cuffs to impede drainage. I love seeing geniuses in wetsuits with water proof latex wrist seal tops swimming and then trying to get up on rocks... please save yourself the agony mr 50 lb balloon arms- dont be that guy!
Have a knife. if you are smart, and swimming in the dark- have 2. you should be able to reach it easily. it should have a line cutter notch so that if you suddenly find yourself off your rock, underwater getting rolled, and are wrapped up in a net or line you can confidently find it, pull it and reach to your left and pull up over your head then down to your right and slash an escape triangle in a ghost net or free yourself from a single pot line etc. practice finding and deploying it always place it in the holster the same way so you know what side the line cutter is on. I keep one on my left shoulder, and another on my calf. Very easy to drop one under duress. you may need to work on some thicker stuff for a bit ( ask me how i know). Get a blunt tip this will lessen the chance of harming yourself. You arent going for crocodile dundee here or rambo think small, short, light and easy to carry and handle You just need an edge, not length. the dive stores online have the cheapest/ best varieties blunt tip titanium ( think- never rinse or maintain) with a positive click lock sheath have served me the best.
2 lights be able to find your backup with one arm in a hurry
Footwear - think about what you have to hike over to get to where you are going, and what you will do when you get there. trucking a mile over slick bowling balls to get to a spot at squibby where you swim 15 yard to get to a rock calls for different gear than a 45 yard walk over sand and and a long swim. if you are dealing with algae and bubble weed - get some metal into your soles or you are in for some 3 stooges falls and a lot of pain.
dress warmer than you think you will need you can always open a zipper, pull open a cuff or neck seal to flush cold water in, etc.... if you are too warm you cant add to your gear to get warmer once you are 1 hour into your walk and 10 mins into your swim.
dont wear cotton stuff! I see so many guys with 400 dollar wetsuits, all the right surf proof gear- put on cotton sweatsocks, BVD.s and a cotton tshirt as baselayer. this defeats most of your insulation strategy. spend a couple of bucks on some polypro under layers and some neoprene socks. do it now and thank me later. cotton has ZERO insulating value when wet and just wicks heat and makes you miserable. Synthetics or wool next to the skin retains some insulation- but more importantly doesnt sap heat. it will also wick moisture on your sweaty hike out. Speaking of which - if you are starting to get warm/sweat/huff and puff/etc on your walk out - slow down, take your suit down to your waist and tie the arms around your waist. Getting over heated before arrival leaves you vulnerable when you arrive at your destination and raise your heart rate swimming, being stressed, carrying gear, worrying about your buddy, freaking out when that seal/log/shark bumps your leg, etc etc etc.... dont stack the deck against yourself before you even arrive If your walk out is more than 10 mins - take a bottle of water and drink it on the way out. dehydration and exertion is a recipe for: poor performance, being uncomfortable, leg cramps or worse that become truly dangerous if you are swimming to far off rocks at night.
dont turn your back on the ocean at night ( this sounds cliche and trite ( if i forget this, about every 3rd or 4th time i try it, i get reminded why. I've been lucky that so far its mostly been minor pain, a little blood or lost gear. I'm a slow learner. Don't be me)
Whatever rock you are on- look around and pick out a place you will try to steer your fish and control it. and a second place you can easily jump down and have a stable place to deal with it. If you are *lucky* all this will go out the window and you will have to deal with a big fish emergency on the fly. Try to think ahead, be aware of what the current tide, terrain, current and hazard situation is at all times so you can deal smartly and safely with surprises.
You up the risk profile exponentially wetsuiting at night. be proactive and responsible. you owe it to yourself and the people who care about you. there are great rewards in challenging nature on its terms and being taught your place in the universe, and the benefits of fish that come with membership in a smaller organization - but no fish is worth getting hurt or worse. keep things in perspective.
Next - lets talk about large things with teeth that go bump in the night