I wanted to ask for your opinions on this for such a long time. The thought came to me when I was reading "The Unfinished Tales" some time ago. There was a note in the book that makes me wonder if there's a substantial connection between the fact that majority of the evil lords from the books were somehow related to Aule.
I also realised that all almost of Melkor's servants and successors were particularly drawn to the valuables: Sauron (Aulendil), dragons, powerful Men who became Nazgul, Feanor, Gollum, Saruman.
I was wondering if the fact that Aule wanted to create his own race, without Eru's consent affected the fate of those who were related to him. I can see a connection here, but I find it hard to describe. It's like Aule's ability to push the boundaries set by Eru a bit too far (even if he sincerely regretted this afterwards) made those, who served him or were worshipping him particularly easier to break and to corrupt. I know that the Dwarves woudn't match the scheme I am suggesting here (beside the fact they were stubborn and sometimes greedy).
Anyway, here's part of the note:
(...)Sauron endeavoured to keep distinct his two sides: enemyand tempter. When he came among the Noldor he adopted a specious fair form (a kind of simulated anticipation of the later Istari and a fair name: Artano"high-smith," or Aulendil, meaning one who is devoted to the service of the Vala Aulë. (In Of the Rings of Power, the name that Sauron gave to himself at this time was Annatar, the Lord of Gifts; but that name is not mentioned here.) The note goes on to say that Galadriel was not deceived, saying that this Aulendil was not in the train of Aulë in Valinor, "but this is not decisive, since Aulë existed before the 'Building of Arda,' and the probability is that Sauron was infact one of the Aulëan Maiar, corrupted 'before Arda began' by Melkor." With this compare the opening sentences in Of the Rings of Power: "Of old there was Sauron the Maia. ...In the beginning of Arda Melkor seduced him to his allegiance."
Saruman, known also as Curumo (or Curunir) was Aule's servant during the time he was in Valinor. After he came to Arda he was known as "Man of Skill", particularly interested in smith-craft. He became jealous of Gandalf when he discovered that Gandalf has one of the three Elvish rings, because he was longing for one.
Sauron was one of the Aule's Maiar before he was corrupted by Melkor and became his servant. He used names related to Aule, when he was trying to misguide the elves. He was also active under the name of Annatar (Lord of Gifts) which suggests he was willing to bribe people. He chose a ring to be an ultimate tool of ultimate power.
The Ring of course attracted Gollum, who perceived it as "prescious birthday gift".
Dragons were known for their attraction to treasures. Of course Smaug is an excellent example of that. They obviously weren't able to make jewelry or other things by themselves, but when they were attacking places they were often choosing places known for their wealth. They loved to collect those goods.
Feanor was the most outstanding gem-smith the Arda knew, and his passion for Silmarills led to a lot of tragedies.