Imho to reduce ressource grinding to avoid above mentioned "quit reasons", corresponding quests would be nice. They should give you huge rewards of items required for building and tell you what you get before accepting the mission. I think at least our players would more likely prefer a T5 quest that rewards you with 10.000 concrete mix instead of dukes and a random item over going into a mine with an auger and afterwards still wait hours until the crafting is finished.
Hmmm, when thinking about it... maybe not even hard to mod? Or are dukes as reward hardcoded? On the other hand, finally picking between some random rewards of 10.000 concrete mix, 15.000 cement or 7500 iron wouldn't be that bad either.
Otherwise traders may have huge offer of these items (and a reasonable price). A trader offering you to buy 300 cement is quite pointless. They should more likely offer 300.000. And the costs should be equal to the above numbers. So e.g. a average T5 quest gives you 5000 dukes and its balanced like 10.000 concrete mix as an alternative, the trader should offer concrete mix like 9.000 cement for 5000 dukes (a little more efficent to choose the cement mix as reward directly).
Would be still more efficient to mine directly as the mission costs ressources in form of amunition and takes much longer, but i guess many people would prefer the mission over grind-mining.
That should be available for all the base ressources. Nitrate, coal, lead, oil shale... , maybe even stone and wood. In would pick even wood from time to time. In our last game i planted a 10x10 woodfarm and it's just anoying to plant 100 trees after every harvest again and again.