well, to search for buried treasures. some daedric shrine got some valued item in them. also, some statue might talk to you and give you quest and you click on the statue. also don't forget to take away the statue offering.
about the machines, I know what the story behind them, just advance your main story further.
about house hlaalu advancement, finish doing quest for lady in balmora first, get all the advancement you can. then go to another lady in vivec city, finish all her quest as well. then go to uncle cassius. he's the one who can give you advancement. if your skill is not up to the mark. just train them then.