I love strong characters who muck things up and then go on to redeem themselves.
I love (appropriate) humour in stories. Ideally they should just be throwaway lines that read naturally (and would been written naturally and not forced into the story).
I love stories when the character overcomes their problems. I generally prefer optimistic endings (not necessarily happy ones but I find grim stories a real turn off. I don't mind the occasional one but given I read to escape and there's enough grimness on the news, I'd be glad not to read grim in my fiction as well).
I love flash fiction, literally snapshots of an incident. (I also enjoy working out how the author might have taken that story further to standard story or even novel length. It makes a good intellectual exercise).