@Mathijs: Sure, they are less cavarly oriented than Rohan, but still Dol Amroth is a part of Gondor, and their cavalry is still spectacular. I however admit that it should be made harder to play cavalry with Gondor than with Rohan.
@Dunedain Ranger76: ...In their worst years, yes, but there is a great example of Dunedain cavalry. The Grey company might be the best unit of all, both infantry and cavalry. (They are not really a part of Gondor though)
@MattTheLegoman: Indeed it seems strange, yet I can imagine the dunlendings riding on wargs. After all they are very rough. However, in the movies they are seen riding horses, so that's more convenient and therefore less interesting for the warg pit.