Hey Kaz,
Ah, we'll make the speed str requirement more clear in the text, it is unclear right now! We should also be able to add armor defense to the descriptions as well (currently I think they do show when you look at them in the blacksmith, just not in your own bag). Frost manual requires 50 intelligence to learn -- we'll get that info added to spell manuals as well.
For mining, it gets easier as your mining skill increases. Some mining rocks contain more copper, while others contain more iron. The entry underground zones have a little more copper than iron. Further into the underground, the rocks get more fruitful, but you'll want to be a higher level before going too deep. I do think there might be too many hounds in the entry underground zones right now, we'll probably reduce them in those areas in the next update.
Thanks for bringing all of this up. We're working on updates to address these as well as what you brought up previously. Should have a small update out later today or tomorrow!