Popularity and variety

When I started writing fanfic, I read several articles about how to market fanfic. One of the more frequent pieces of advice was to write one character/pairing exclusively if you're just starting out. I broke that rule. Sometimes I wonder if it did affect my readership. On the one hand, I think I'd go nuts if I wrote nothing but Luna or H/L, but I worry about disappointing people who friended me or put me on alert on the basis of my MWPP fic. Does it bother you if an author writes a variety of characters or pairings?