Oh this is a cool idea.

You can do a whole campaign story centered around coming out of a Dark Age.
Let’s think of a new campaign title—something like “Light Emerging out the Darkness”
Now since we want to center our theme of New Technology that Brings Light in an Age of Darkness, so let’s think of some of the major creations that our technology will be and then we’ll discuss some threats.
First up, the gun. This will obviously change the face of war. Let’s make this item a non-magical item. Anyone can make a gun with the right components and anyone can be trained to fire one.
Second, the airship. Now we can make this magical, but it’s always been a common theme to make an airship somewhat arcane in nature such as a wizard invents one, or that an elemental is bound to it, etc. So let’s make this unique in that not choosing any of these. Let’s say there is a special material called lightstone that can be mined deep in the Underdark that causes things to float. The lightstone itself is quite magical and to bond it to the ship to get it to float is a magical process, but anyone can pilot the ship with skill and training.
Third, the telescope. Beings are able to see the other stars, moon, and planets with greater clarity. They also can the other constellations in the sky. This is a non-magical device.
Now we have three inventions in which will come into play during our campaign. We can invent more, but we want to create a theme in how the world views them. So here’s a possible way we can break down our campaign.
Levels 1-3: A War Synopsis: The PC’s are part of a group of adventurers hired by a noble to go to a secret location that is dedicated toward a war effort. This could be a war between two duchies, baronies, or nations. The PC’s go the location which is located in a monster-infested woods and is a set of ruins for the PC’s to explore. They find out that this location was overrun by monsters at the behest of the Guild of Magic. The PC’s have to free the prisoners, defeat the monsters, defeat any Guild of Magic representatives, and maybe assist with weaponsmiths and alchemists who are making a new kind a weapon—the arquebus.
Enemies: Monsters from the woods, goblinoids, and the Guild of Magic.
Motivations: Monsters get food in the form of humans and dwarves. Goblinoids get shiny coins from Wizards. The Guild of Magic is threatened by the power of a gun that can be wielded by anyone. They want to win the war, but to not have any technology that threatens the status quo of using magical means of wiping out one’s enemies.
Conclusion: A lot of guns get made and the enemy loses a major battle and then sues for peace. The PC’s are war heroes. Members of the Guild of Magic are arrested, exiled, etc.
Levels 4-10: Airship Campaign: So we break this up into a couple of parts:
Part 1 (Levels 4-6)—the PC’s are hired to go into some remote mines to deliver a large payment of gold in exchange for lightstone. The PC’s have no idea what lightstone is or does since no one has ever used the stuff. The PC’s get to the mines and find out that they are completely abandoned and deep. The PC’s explore around, fight wandering monsters, and discover evidence that the dwarves that lived in those mines were attacked and their bodies taken deeper into the depths. The PC’s begin their journey into the Underdark and the adventure ends with the PC’s going to a drow outpost and rescuing the survivors.
Part 2 (Levels 7-8)—the PC’s know that the drow were working with some kind of alliance of monsters and cabalists over the lightstone. They learn what it does, but they don’t know its possible applications. The PC’s track the alliance and puppeteers through the Underdark to some surface ruins far away from their home. They also find some Guild of Magic mages who were captured and tortured for their knowledge of lightstone. Apparently the alliance plans to use the lightstone to lift a castle in the sky so they can have a base of operations from the air (who can fly and oppose them while in the air?). At the end of this part, the castle goes up.
Part 3 (Levels 9-10)—the PC’s now use the help of the freed mages from the Guild of Magic to create an airship, go into the castle and defeat the terrible evil ready to be unleashed on the surface below. The PC’s have to explore the castle.
Note: If you had the PC’s enemies of the Guild of Magic before, they are likely to be considered “even” with the Guild for rescuing members and assisting with the invention of the airship.
Levels: 11+ War of Interpretation—A famed mage and devoted cleric of a God of Magic creates the telescope. He scans the heavens, makes incredible discoveries about the stars, the world, and writes and publishes a book that challenges the assumptions of the many interpretations of both magical and arcane thought. At first, no one thinks on the matter, but clerics begin to receive angry visions from their gods about this perceived slight. The God of Magic is doing what he can to protect his follower, but there is even a schism within his own church because of the challenging assumptions of the world. A rival, yet large sect declares war over the heresy. The PC’s have to find some way to appease the gods, protect the cleric, and avert a religious war.
Okay, there you go!