We all have things we are drawn to. Don't fight it, it is natural and a great tool to help build a portfolio. Why try to fill up your image bank with things that interest other people and not yourself. You know what things they are, they come naturally, easily and fill you with satisfaction.
Me, I likes me shiny things,
some well lit architecture, not necessarily classical, but eye catching,
working details within the bigger picture,
finding abstracts and "distilling" images not seen initially,
busy streets full of people, just being people,
and boiling skies.
Follow your heart, apply your head and trust your gut.