I feel your pain on this issue. I have been playing as a sniper for lots and lots of years. Everyone wants to talk about gillie suits no one wants to talks about belly crawling and the kind of gear that you need to have to be good at that. Before I start, let me say that even after years of searching, I haven't found the perfect solution. I'm not convinced that such a thing even exists.
By way of background, I have played with a T9 with a first-strike conversion kit for years. It became a back-up to the T9.1 about 1 1/2 years ago. I also recently added a CCM SR1 to my list of guns. I also carry a T8 whenever I am on the field. I use first strikes exclusively.
I reason I don't believe that you can find a perfect equipment answer to your question is because gear has to match the mission. The SR1 is perfect for some jobs and not so well suited for others. Vests and pouches are like that too. Before every event, I checked in with whomever is generalling the event and find out what it is they want me to do. Those assignments range from crawling all the way through enemy lines to shoot the other general to staying back and guarding my own general and his HQ from sneaky snipers to prevent them from taking him out. Once I found out what it is I am supposed to do, then I determine what gun and gear best fits the task.
For example, if the mission is something requiring mobility, like moving behind my own lines and radioing intelligence about what is happening on the field or at a particular battle (more times than not that is what the general wants) then I need to be moving, mobile, and carrying a lot of ammo to help out where I am needed. That means a Blackhawk vest with lots of mags and the T9.1 with its short barrel and tactical foregrip that converts into a bipod. I certainly can (and have) belly crawled dragging the T9.1 but with intelligence-type mission I don't end up doing much of that.
If the mission is going deep behind enemy lines to take out a specific target or retrieve some object then I will be spending a lot of time on the ground. For that kind of thing I will use the SR1 if the object of is shooting, or the T9.1 for retrieving or scouting. I will shed the Blackhawk and use the Spec Ops P3. Everything on the P-3 (except the dump pouch which I often just detach) is on the sides or back mounted on a belt like arrangement. I couple that with a camo hydration daypack by Camelbak. I always use the tactical suspenders with the P3 because it better supports the weight of my mags, radio, and tactical leg holster.
I always wear a Webtex Concealment vest cut-off at the waist. It is made of a green mesh with attachments for some rudimentary strips of camouflage that stay on it permanently, but it also has a large number of places for vegetation which I start working into the vest as soon as I am on the field. The vest does not cover my chest area. It is meant to conceal my back, shoulders, upper arms, and (with the detachable sniper hood) my head. Unless high temperatures make it impracticable, I always wear it, just stripping it of veg. if I am doing something that doesn't require it. After wearing all kinds of gillie suits and 3d camouflage, I have found that I can do everything I need to do with just the Concealment Vest fully vegged out.
My blog site has pictures of all of the stuff I mention here. I am not saying that my stuff is the answer to your question. It is just the way I have resolved the issues for the way I play. Good luck in your search.