So, organizing your loadout - what's the big deal? If you, like me, were in the military (United States or elsewhere, I guess), you likely had a packing list for your assault pack, your ruck, and a certain list of items you had to have on your person at all times. For me, my platoon sergeant wanted me to have a notebook, three pens, the Ranger Handbook, a watch (that worked), a knife of some kind, a multi-tool (could double as the knife), my dog tags, my wallet with military ID and driver's license at a minimum, and there's probably one or two things I'm missing. Holy crap, that's a lot of items, but I always had a system as to which pants pocket and uniform top pocket was carrying which item, so when it time to write notes during a brief, I knew to go right to my bottom right pants pocket near my ankle and grab out my little green notebook.
Fast forward to civilian life, I don't have a boss that tells me to carry three pens and ten other items, but I still like to have some sort of organizational system for my first line, my plate carrier, my bugout bag, my three day pack, and anything else that I may be taking to the range, to the mountains, or wherever else. This isn't an ad telling you to buy one pack, pouch, pocket organizer, or whatever over another, but I will tell you what has worked for me, and what I can recommend for you.
For your first line (AKA, your belt setup), I wouldn't recommend anything larger than a ZAP, or something like a belt mounted general purpose (GP) pouch. I don't like to carry much outside of the essentials on my belt (holster, mag pouches, IFAK/TQ, and maybe a knife). On your chest rig/PC is where you can really get into the 'immediate action' administrative type stuff, though it still depends on your role and usage. A PC is a great spot to have a larger admin pouch or some sort of organization system, and some plate carriers even have a velcro or zippered section where people store things like maps, route plans, etc.
The bottom line of this post is, get organized. It doesn't mean you have to buy anything - use Ziploc baggies for all I care, if it works, it works. My kit back in the Army utilized probably 10 different Ziploc baggies - one carried my batteries, one carried some spare pens, one carried some snacks, etc., just have a system. Get yourself organized sooner rather than later. This includes your range bags, your go bags, and whatever else you've got that may be grabbed.