I'm a big advocate of doing short term wet or dry aging of meat prior to freezing or other processing so it has time to come out of rigor mortis. There are two exceptions , grinding or canning the meat, in both cases the meat doesn't need to age to tenderize as grinding and canning processes take care of that. There's a section about this topic in my ebook
Backyard Butchering with Laurie Levey - Rabbits.

Every year I cull a number of older rabbits that are anywhere from 9 - 36 months old. Any of the meat from these older rabbits that I don’t intend to grind is dry aged to naturally tenderize it. Once they are properly dry aged, I can do anything I want with the 7-8 lb dressed out rabbits, including throwing them on a hot bbq without any additional hydration for a summer cookout. The meat will be as juicy and tender as you’d expect from a younger rabbit and it will have with enhanced flavor from the dry aging process.
Aging meat is an old school practice and something most of us need to relearn. It's not tricky, but most of our homes aren't set up for properly aging meat anymore. Confined feed lots (CAFO) practices have made buying small quantities of packaged meat for a low price easy, so easy that we got away from raising and butchering our own meat. With that basic living skill removed from our lives, we started living in dwellings that don’t take meat processing into mind when they’re built. The other thing CAFOs have created is a deep fear in us about the safety of eating meat that's been properly aged. I too would hesitate to age grocery store meat for a long time without very strict conditions, simply because I don't trust that the meat was handled well before it was in my hands, or that the animal it came from was healthy to begin with.
My home grown animals are a different story. I know how they lived, what they ate, if they were subjected to abnormal stresses in their environments, and if they were I would have rectified that quickly. I don't trust that to be the case in a CAFO situation. With home grown animals, I ended their life in a fast and humane manner, skinned and gutted them, looked at their internal organs which tells me a lot about their physical health. I can smell the freshly butchered meat as I work the body and feel it with my fingers, utilizing both the sense of touch and smell to determine if everything is as is should be with the meat. I know the quality of the meat I've butchered so dry aging it for long periods of time doesn't give me any health concerns. Personally, I don't trust the commercial meat industry to make sure only healthy animals with uncompromised meat make it into packages that we can purchase at grocery stores.
I do believe grocery meat is acceptable and safe to consume if handled and cooked properly when you get it home, and the USDA has made sure we all know what those safeties are as they are listed on the packaging, yet that's also the source of the belief that all meat needs to be handled the same way in order to be safe to consume. When in fact the ‘safe meat handling’ practices are there as a broad, inclusive recommendation so meat from stressed out, unhealthy animals can be sold to consumers.
When I say unhealthy I'm talking about the ill health from stress alone. People who are experiencing stressful conditions for long periods of time have compromised immune systems and often develop health issues due to their low immune response. Usually their health issues are remedied by removing the stress that caused the issues in the first place. Animals are the same. A stressed out animal that doesn't have a healthy immune system is likely to have minor illnesses brought on by a compromised immune system, and it's enough to degrade their bodies, which compromises the vitality of the meat once the animal is butchered.
Back in the day, when people were eating meat they obtained through hunting, fishing and raising themselves, they were much more relaxed about how they stored the meat and for how long. I have seen a picture of my grandmother that was taken sometime in the late 1930s, in a downtown business district of a big city, standing in a corner butcher shop picking out a chicken to buy. The chickens were plucked and gutted, the heads and feet were still on the bodies and they were all hanging by their necks in the front window. That was a common practice and it wasn't thought of as odd and unhealthy, it was also before we all became accustomed to packaged grocery store meats that comes from CAFOs. Now, leaving a hunk of meat at a moderate temperature after butchering for even a few hours can make people so nervous that they put it in the freezer right away, or cover it with ice as soon as it’s gutted and cleaned to keep it as cold as possible until they can get it into the fridge or freezer, which creates the condition of the meat being tough when it's finally cooked.
I do follow many USDA guidelines when I'm salt curing meats. I know the conditions that botulism is prone to grow in, an environment that's oxygen free, slightly acid, warm & moist with the high danger zone being 78 - 95 F. I know it cannot be seen, smelled or tasted if it's present. I don't mess around with that when it comes to curing meats, and since I'm not afraid to consume nitrites and nitrates, I utilize them in safe amounts to prevent botulism from occurring. When it comes to dry aging meat, I'm a bit more relaxed.
When dry aging meat, enzymes present in the meat are breaking down the muscular structure. The longer it ages the more the enzymes can do their work of collapsing structure, which is a natural tenderizing of the muscle meat, it also creates concentrated flavor in the meat that you won't get any other way. As the meat ages it starts to have a strong smell which is normal. We’re not use to smelling properly aged meat, so the smell can make you wonder if something’s gone wrong with the process, it made me wonder that the first time I did it.
Most people only have household refrigerators to utilize to dry age meat in which has a temperature setting of around 34 - 35 F. That temperature works fine for dry aging any meat, even grocery store purchases. Back in the day, people had sheds near running creeks on the north side of the property that stayed cool that were utilized to age meat in, or a cellar under the house, or something similar built into the hillside where the underground temperatures were many degrees cooler than the surface temperature is. They had ways of hanging meat, just like the chickens in the butcher shop my grandmother shopped at, that allowed for full air circulation around the meat while the juices drained away from the body as it hung. It was only after a certain amount of time hanging for natural tenderizing and flavor development that they took the next step in processing the meats.
Rabbits, being a small animal, are easy to dry age in a home refrigerator, and I have found 7 - 9 days of dry aging to be long enough to make even a heavily muscled, 3 year old rabbit tender. The temperature in the refrigerator is already controlled and low enough to be in the safe temperature zone, but not so low as to slow down the process. The only other things you need to do are to make sure the rabbit has full air circulation around the body and the juices drain away from the body. If you have a second refrigerator in your garage it can be rigged up to hang rabbits by the rib cage with a pan under the meat that catches the juices, that’s the easiest way to get the aging job done. If you need to rely on your kitchen refrigerator, you can lay the rabbit on a wire rack with a pan or bowl under the rack to catch the juices. If you’re laying the rabbit on a wire rack, you want to lay it rib side down, spreading the belly flaps and hind legs open as much as possible and arch the back at the base of the rib cage so all the juices being released during the aging process drain away from the body. That’s it. You can go a step further and have a spray bottle of a 50/50 water/vinegar solution to lightly mist the meat with every day as it lays on the rack or hangs by the ribs. The vinegar/water solution will help to keep any unwanted bacteria from forming on the surface of the meat, and will also help to keep it from drying out too much.
The obvious problem with dry aging a rabbit in the kitchen refrigerator is how much space you have to get it done, and how far away you can keep it from other foods and containers in the refrigerator so they don’t end up spilling on the rabbit or interfering with the full air circulation. I’ve made temporary walls out of cardboard that I placed next to a rabbit, so all the foods and jars in the refrigerator never came into contact with the meat, I find that an easy solution for the issue.
After the 7-9 days are up, remove the rabbit from the refrigerator. The outside of the meat will feel dried out a bit, if it’s been laying on a rack the belly meat and hind legs will have the impression of the rack in the surface of the meat, and that most likely won’t go away. At this point you can cook or cure the rabbit meat in any manner you like. With the flavor of the meat being enhanced from the dry aging process, it’s nice to utilize the meat is a way that show cases that flavor.
The first time I tried properly dry aging a 3 year old rabbit for 9 days, I cooked it in the sketchiest way I could think of to see if it really was as tender as I was told it would be. I took it from the fridge and was immediately skeptical when I noticed how dry the outside of the meat was. I rubbed it with salt and pepper and tossed it on a hot bbq like it was a fatty chicken. I cooked it on both sides then hit it with a little bbq sauce at the end, just for that bbq flavor. Much to my surprise and delight the meat was exceptionally flavorful, very tender and even juicy.