Must Play Champions?

Im new to this game and currently I main Singed and he is the most fun champ I've played so far. I like Sion but games with him are really slow, I also play Annie and I like her combat style but I don't like the fact that she is so squishy. What champs would you recommend for someone like me? I hate playing Kayle and Soraka. Lissandra was a lot of fun but I don't own her yet.