Exploration is probably a bit slower than in Civilization 5 since infantry have a speed of 1 and you have to be careful about planet life pillaging your city instead of just letting city defenses do the job. I rather not comment too much on the pace, it would just end up being deceiving. For me turns probably go faster than for the typical player since I've been working on it, and how many turns a typical game lasts is still changing a lot; the AI improving and so on. The tech tree is long enough to not disappoint in that regard.
City specialization is mainly encouraged by territory resources, buildings and position. There are currently 7 stats you are going to care about on a city scale and 4 of those resources on a global scale. Food, minerals, research and credits are all global and available or lacking to all cities. Food is required for growth, but excess food does not speed up growth. Minerals are required for production, research for new technologies and credits for purchasing and paying upkeeps. In the city you'll be gathering food and minerals from tiles while also assigning colonists to production and research. Production directly consumes minerals so those are tightly linked together. Credits you gain are mainly based on the city's population. The other two stats are morale and pollution. Morale decreases with negative effects such as pollution and overpopulation, and provides an overall boost in everything your colonists do, as well as increasing the growth rate. Pollution is a negative stat and increases depending on how much food, minerals, production and research a city is producing. Once enough pollution accumulates it pollutes a tile and it becomes unharvestable until cleared.
The economics are certainly not as focused as in a game like Colonization, which has a bunch of different goods while just 4 types of military units, so don't go expecting that. I really like Colonization's mechanics, I loved the original, and we've actually been playing Civilization 4: Colonization a lot the last days (too much actually), but Pandora isn't that. It's more tactics and operations and warfare, and less economics. On the other hand, Colonization's buildings are limited in usefulness to each city and production itself is not as focused so you don't get very excited about buildings, while in Pandora I just end up wanting to construct a bunch of buildings in each city. The economics of Colonization and the warfare of Pandora together could be very interesting. Food for thought for another game.
Conquest was a very different beast, we wanted to do competitive multiplayer with that, while Pandora is focused on the single player experience. I'm really happy you liked the engine.