My RE put me on Letrozole initially, it is supposed to be better than Clomid as far as not messing with your CM and altering your hormones as much (which sometimes can trick you into not producing enough of certain ones)
However, I did not have a good response to it, only had one good follicule and I O'd later in my cycle than normal (around day 18 instead of 14) but I supppose different people respond differently. My RE told us we could do Letrozole and BD on own. But, the next month, he switched us back to CLomid and we had to do IUI with Clomid because of the mucus issues.
Hope that helps, and best of luck to you