Trousers/work pants wise I wear modernised BDU style ones from a few companies or hunting brand ones when it’s colder.
Pentagon/Helikon/Truspec/Solognac. I’ve had 5.11’s but never found them that robust as they always fail in the same place for me.
The military style ones I get in a solid colour and a version that has smaller pockets inside the main cargo pocket as I don’t like loose stuff rolling around in them. Also in the winter I have space to stuff hats and gloves (plus shoe flask gin) in.
What I usually have on me apart from keys/wallet/phone.
The knife and taped up bag of tinder & lighter plus a cravat bandage are what lives in the pockets. I can usually stuff a windshirt in cargo pocket with some pilot gloves.
Four pocket canteen cover carries a lot. I’m tempted to give the Helikon essential kitbag as a bit more versitile. But I had the canteen longer than my offspring so I don’t want to change it! Grenade pouch will hold a light waterproof but usually has small tarp, cordage, pegs, notepad and pen. I don’t often carry a big knife unless I have a project in mind, then I will have a 5-7L waist bag of stuff.
The contents of the two pouches will fit in a smock quite easily. I stopped using mine when I was more often in town working than the countryside. Also I found it more convenient to take off a waist pouch to go through stuff than remove my smock to get in the poachers pocket.