Giz,
I'm not sure there are many people who think of themselves as extensively following both trades of the Horner and Leathersmith, though I could be mistaken. I think perhaps some Horners make some pouches and some Leathersmiths make some horns. If one is really going to get into working either "trade," it often requires spending a lot of time on making tools or buying them for either trade, even when it is a serious hobby.
I got into Amateur Leatherworking because either some items were not available or I wanted to do something "custom" to my or other's desires. I made a few horns for myself and friends, but I am no Horner by any means. I don't consider myself a professional leather worker, by any means, either.
My first leather shooting pouch was a horrible failure as it was made of too soft of leather and was not authentically made, though it looked "OK." My second pouch was not extremely professional, but very nicely done as I had learned a lot since making the first and took some time to plan it. I set it up so I could use it to shoot either Flint Rifle or Northwest Trade Gun by switching some accessories. Could not afford two pouches at the time even though I made them myself.
My first and really only complete leather "Accoutrements en Suite" were those I made for myself when I switched to doing an UnCivil War Officer's Impression. I wanted something fancier that an Officer would have carried, so I made the leather goods and used Original metal parts. I found a later 19th or early 20th century M1850 blade that was a "REAL" combat blade for sale, so I bought that and gathered original parts for the Grip and Scabbard and assembled my own sword and scabbard. For some time in the early 80's, I was one of the few, if not only Confederate Officer carrying a real M1850 style sword in reenactments around Virginia. Then a few years later, they started making repros, but not the same quality of blade and other parts as an original or the one I had assembled using original parts.
When I got into doing a Private Soldier in the Black Watch in the late 90's, I made most of my own leather goods (except the Belly Box) both to make better quality goods than generally could be found from the Sutlers and in a couple cases to make them more historically accurate. Never made a Sporran before, but a Private Soldier's Sporran was not that difficult.
Most of the leather goods I have made over the years for sale or trade were military goods for Rev War, War of 1812 and the UnCivil War - when those items had not been correctly repro'd or not made except on a custom basis.
Been making plans to make an 18th century "Accoutrements en Suite" and got inspired by James Rogers' Superb set he recently posted. My set won't be quite as fancy as that, though. Grin.
Hope I haven't wasted your time, Giz, but since no one else answered yet, I thought this might get the discussion going.
Gus