@SteveAdamo has already addressed a couple of these, but I’ll just lump everyone into one response 
We’ve only seen a small amount of weaponry so far - I would imagine a wide array of equipment to choose from, either through the vanilla game, or a mod pack - a weaponry mod pack is one of those things I expect to happen relatively early on
The combat system is something that by the sounds of things has been reworked quite a lot, like Steve has said we saw a very early prototype of the combat system - the proof is in the pudding I guess, and we’ll have to wait and see what they have in store for us!
That specific first question isn’t something I think we have a direct answer to … and I’m not sure if I want to commit to an answer … with the AI building up a settlement that would seem like they are directly competing/ growing with you, perhaps pre-built for you to uncover is the way it will be.
We know that the end goal is an essentially infinite world where you will never reach the boundaries - most of your time will be spent focussed on your settlement, I think exploration of the world is one of those things not set in stone yet, but I would hazard a guess that yes you will uncover them as you explore, or perhaps they will uncover you?
There’s a discussion about this over here, right now all things are indicating that you don’t have a ‘personal’ character - you are more the orchestrator of the settlement rather than an individual character, customisation will be a massive part of the game so rest assured you can customise characters and buildings quite extensively I imagine.
We’ve had a few discussions about trading and things like that - I’m swapping internet at the moment and am using my mobile as a connection so it’s a bit awkward locating the posts but they are there.
The thing with this, and the discussion has been raised in the ‘king’ thread - is that this then dictates to you a system that your settlement should have, perhaps not everybody wants a sort of feudal system in place.
Settler’s become specialised through their jobs so to then differentiate between this and a sort of caste system would be a bit problematic?
Families and aging has also been discussed [here][2].
In terms of technological development, again we’re not sure quite yet what the system will be, and I can’t think about what we’ve been told in regards to this - your example reminds me of civilization and i’m not sure how/ if that style of progression would fit in with the game, I’d reserve comment and judgement until I’ve played. Perhaps a system where you are limited by the materials at hand and the skill of your units rather than researching specific technologies would work better? Who knows.
Aaaaaaand I’ve been ninja’d by Voxel Pirate, never mind, it all still stands!
[2]: Thoughts on Children and Population Growth[quote=“Spododo, post:4, topic:3723”]
The combat is a little bit like in Timber & Stone.
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Well, we don’t know that quite yet, I don’t think it’ll be quite like Timber and Stone, without a working model of what to expect it’s difficult to compare - I suppose the original system we’ve seen is a faster paced Timber and Stone system.
As far as I know this hasn’t changed … you have the ability to choose from a predefined ‘blueprint’ or a freeform construction … although I might actually be wrong here ( @voxel_pirate @SteveAdamo please correct me).
In terms of mining - the underground itself is (hopefully) going to be as fleshed out as the overworld, that’s all we know about mining, whether we are able to dig around underground, or have ore veins that we mine is yet to be seen.