I'm afraid I don't have children of my own so I can't speak to that end of the spectrum. However, I do recall my own parents and their methods when I was growing up.
They were never permissive from the very beginning and it was abundantly clear that when Mom or Dad said anything, we were to listen. Of course, occasionally, as little ones do, we'd get out of hand from time to time. But overall, the parents ruled the roost and it didn't take an iron fist. There was a three day rule in our household. Neither Mom nor Dad ever told us to clean up our bedroom or playroom. Rather, if a toy stayed on the floor for three days, it would end up in the trash by the fourth and no begging or pleading would change their minds. I can assure you that, as much as this may have been a painful lesson, it was a lesson that was well made. We were always neat and always put away our toys after losing a precious item once or twice.
This belief has carried over into my and my brothers' adulthood. Our wives, partners or fiancees have never had to clean up after us. We've never left a mess behind. We do the dishes and help with the house work. In fact, I straighten our apartment every night before I hit the hay. Putting the dog's toys back in his basket. Straigtening the couches and pillows, cleaning up the dishes and emptying the dishwasher. Anything that had been draped over a hook or chair, from a briefcase to a robe or coat, is put back where it belongs. Hats on doorknobs are replaced back on the hooks. Counters are wiped down, blankets are folded up and put back in their basket, shoes by the front door are straighted and organized, the towels to wipe the dog's feet are refolded, and on and on. It actually never takes more than 15 minutes each evening to do what is necessary. And I never ask my partner to help. I gladly do it because it needs to be done.
See what strong but loving parenting does? It engenders a stable, organized, neat adult.
I may have thought Mom and Dad were "mean" when I was a child and I lost a toy, but that was always shortlived. As an adult, I have nothing but love, admiration and respect for my parents. They raised my brothers and I in a happy, loving and NEAT household!
You're doing the right thing. Keep it up.