No one is going to count every torch and report a single torch or block out of place and then get you banned for a single torch. As far as the wastes go, it's okay if you cut into other mining tunnels as long as you leave walkable paths. You can't just mine a block or two in the wastes and then claim the whole area as yours. The general rule is that natural structures in the wastes are free game, leave player made structures alone. If you get creeped near a player structure or a road/path it's generally good practice to fill in the damage. And if you want to mine diamonds I recommend " branch mining" / exploratory mining at depth 10-11. (Google it)
