I've been struggling with this because I've been diving a lot after work lately. The biggest problem is that most of my dives are after work night dives, by the time I get back, drive all the way back home and get the gear out it's pretty late and I have to get up before five every day. It's much easier to keep my gear in the giant tote in my suv and just deal with it in the am at work.
There lay the problem, on open or slick cell wetsuits, the funk that grows with all the piss and oils gets pretty bad. Normally my goto is to soak my suit in antibacterial dish soap (I also use a diluted form of this for my lube as it keeps the folliculitus down). But even after a soak, the cooler weather has made the suit extra funky. I tried adding a little bleach but it didn't help that much and if you use too severe a solution it will damage the color and the rubber itself.
I started doing a lot of research, sink the stink makes little bottles but that ain't going to cut it for the amount of dives I do. The main thing you want is something with an enzyme in it that helps deodorize, the problem is most readily available stuff also has nasty chemicals in it that could damage the suit and could damage your skin. Having lost more than my share of family and friends to cancer, I'm starting to be a little more cautious about chemicals in my life...
I came across some old scuba threads about using "Natures Miracle". I've used this a ton of times since whenever I have a puppy they always end up making messes in my house during the house training episodes. A quick look into the ingredients and it has the enzymes in it and is mostly safe except for some isopropyl alcohol. Further research, the alcohol will damage neoprene BUT since I mix my soakings with about 10 gallons of cold water I figured I'd be safe, plus I go through suits every 2 years anyways.
My recipe is simple, I take one of those giant party buckets from walmart etc and fill it about halfway full with cold water. You never want to use hot water on a suit because it damages and shrinks the rubber. I mix this with a squirt of the natures miracle and then soak the suit and all my neoprene with my weight belt on it. I leave it in there for five minutes and if the suit is extra stinky will add some soap and let both mixes soak the suit for up to a half hour. If you do it too long I notice the glued seems turning white and that's not a good thing. I have wetsuit dryers that I made out of pvc and I dry my suits in the garage.
So far so good, it eliminates maybe 95 percent of the smell. I repeat this only when the suit is ripe, usually about every three dives in my case, in the other times I just use my soap recipe.