I started with the idea that I wanted all of this stuff to work together in a modular, layered fashion.
The theory is that having a different rig for every rifle/shotgun and/or different scenarios is not only expensive, it is impractical and cumbersome. By running gear in lines, I can eliminate a lot of problems associated with that. I'll go over each level with an individual post.
I start with first line gear, which is basically a pistol. This is the base for everything else. With the first line, I can support the pistol. This is roughly parallel with an LE duty belt. It is in its purest form intended to carry needed items for the pistol and that's it; in a .mil role it would also have some E&E kit. A fixed blade knife is also frequently present. Prior to warbelts, it was usually a heavy inner belt/pistol belt that was worn with the belt threaded through the pants belt loops and allowed the wearer to take the other webgear off and have the pistol still on the person. It was often a drop leg rig, or a slightly modified drop let rig so that it would clear armor. Now the warbelt has arrived and is increasing in popularity. The warbelt rig is also frequently a drop leg or modified drop leg rig, again in order to clear armor, chest rigs, or whatever. Because I'm not wanting to always have a holster on my trouser belt I went with a warbelt.
The warbelt also allows me to carry more crap comfortably, and I don't have to worry about removing the holster to put the outer belt on. The SGPB is the best way I've found to carry the gear I want to. It is wide enough to keep from being uncomfortable, the soft lining helps to keep the belt from sliding or jumping. The platform has lots of MOLLE to carry stuff, and the inner belt tunnel provides a good base.
On my belt, I chose to also support a rifle or carbine. This was done because typically if I'm just going to carry a sidearm, I'm probably going to be using a duty type holster or simple Kydex RCS rig with one spare mag and a light and I'm not going to worry about something like a warbelt. So I put two rifle tacos on the belt to let me run a biner.
Going counterclockwise on the warbelt, I run a SF E2D light at the front left. This is like the light I use at work, which is the E1B. Behind this I have the two tacos, which will work with a range of rifle mags and even shotgun cards. On the front taco, I have a TacTailor dual pistol mag, again positioned where it would be roughly on a duty/concealed belt. I dropped them down one row so that the mags would not interfere with pulling the rifle mags. I went with two rifle and two pistol mags becuase that is pretty much all I'm going to need. For classes, there is usually time between strings to get another mag if I need to go through more than three, and I can shove one in a pocket if I have to. Also, the third taco that I tried at first conflicted with the corner of my rear plate. The Micro/ASB will also be available if needed because of the layered intent of the rest of my gear. Behind the rifle tacos is a Maxped RolyPoly. This is for retaining mags or to put a Nalgene bottle in if I need to stow some water. Next is the OSOE CAT2 deployable pouch. Philosophy behind this is that if you're going to have stuff to poke holes, you probably should have stuff to plug them too. I used to have a TQ here just shock corded through the MOLLE loops. It worked OK, but it wasn't real secure. With the pouch, the TQ is protected and will be there when I need it and the security will make it ready to get to without being overly combersome. Next over is an HSGI Bleeder Pouch. This is a great kit, and again a hole plugging thing. SOF CAT is stowed on the outside with shock cord. Having more than one TQ can come in handy if things are really bad. If you have wounds to two extremeties it is an obvious solution. However, on large vessels such as the femoral having twice the clamping area can help to staunch blood less much more securely and efficiently. The inside of the Bleeder has the main TEMS stuff, and a pair of EMT shears are held in place with a security strap built into the pouch. Next thing is a G Code holster with RTI adapter. The adapter lets the pistol ride slightly lower than a belt mount, and not so low as a drop rig. This way I can clear my armor and chest rig without having the PITA factor of a drop leg mount. The RTI wheel also lets me have a couple of holsters that I can switch out depending on pistol or belt rig, and if I want a light mounted pistol or not. Next is a Leatherman MUT, a multitool designed for the AR platform. I have a CATM4 tool wedged in the side of the pouch too. This is the extent of PMCS gear on the warbelt. Forward of that is an ITW carabiner. I can clip earpro, gloves, or whatever to these.