What did they think?

[Galadriel55]

Tolkien compares Aule and Morgoth in the Valaquenta (The Silmarillion):

Melkor was jealous of him, for Aule was most like himself in thought and powers; and there was long strife between them, in which Melkor ever marred or undid the works of Aule, and Aule grew weary in repairing the tumults and disorders of Melkor. Both, also, desired to make things of their own that should be new and unthougt of by others, and delighted in the praise of their skill. But Aule remained faithful to Eru and submitted all that he did to his will; and he did not envy the works of others, but sought and gave counsel. Whereas Melkor spent his spirit in envy and hate, until at last he could make nothing save in mockery of the thought of others, and all their works he destroyed if he could.

So indeed the making of the Dwarves cannot be compared to the making of the Orcs. Aule a) made his own creation and b) gave it up for Eru. Melkor a) marred Elves and b) did the most hateful deed to Eru (there's also a quote about this but I can't find it).

What did Morgoth think of Orcs? Probably he didn't really care about them very much (like Sauron) - he had plenty to spare.