On the subject of equipment, what TL is Felltower?
DF is technically "TL Olden Times." That's a cute way of saying it's a mix of TL0-4, lacking gunpowder, with everything mixed together. Stone clubs and edged rapiers exist side by side, as do bone armor and full plate. People arm themselves with a weird mix of gear - bronze swords carried by men in mail, fur-clad archers use composite bows with bodkin point arrows and tote the finest steel cavalry sabers, and so on.
Felltower owes most of its technology to this weird mix.
Some things are a bit more advanced, thanks to Gnomic technology and Dwarven metalwork. The game still lacks gunpowder, if only because of the consequences of allowing PCs to buy kegs of black powder* on the game as a whole.
A lot of the "technology" that is a bit ahead of its time are social inventions. The PCs are literate. Books are expensive but aren't crushingly so. Guilds exist but function a lot more like unions than orders full of secrets. Magic is handled in a relatively perfunctory yes/no availability fashion. The city is organized around a mayoral system and has both guard and watch. There is no banking system, exactly, but only because I chose to handwave in-game in-town risk to goods. If I had that risk, I'd have a robust and fairly modern banking system. Socially it's a very egalitarian place except for social stigmas against criminals, outlaws, barbarians, and monster types. Those aren't legal, just norms. There is no slavery. Healing, both magical and reliable, clean, infection-free non-magical, is available readily.
Most of this is a function of allowing the assumptions of the players to work without the game presenting difficulties. The goal here is dungeon delving, and all of the above allows for that to take place with minimal outside impact.
Hard tech and soft tech are both limited to those things that are non-disruptive to the main aim of play, and also both raised to the level that is most conducive to that.
* In short, it's not guns that are the problem, it's solving every problem with Ignite Fire and kegs of explosives.