I LOVE KENNEN AND TRISTANA ♥♥♥♥
I unlocked Tristana when I started out to pad my character count, thought she was super qt and all that, but when I tried her vs. bots I realised she's just an absurdly fun character. Same for Kennen during his free week -- I'm saving up for AD carry runes, scaling mana regen yellows, Miss Fortune, and Kennen now because they're so enjoyable to play. I guess I like things with good laning phases in general, because in normals nothing ever gets to lategame zz but Tristana has a ridiculous lategame anyway and Kennen still brings THAT ULT to the table.
I kinda have a rule where I only play cute or fabulous or pretty characters haha... I think Fizz is very cute! But I'm all about yordles. :>
Lulu is amazing to play, and she can do anything (though I have never tried her jungling lol >__> not sure how her clear would be but she would have amazing ganks because of all her CC -- even roaming with her as support can set up some good kills). Aside from her kit, which always keeps things interesting via the amount of options it presents at one time, she has the cutest laugh and she's so sparkly and hnsdgjdflgd EVERYTHING ABOUT HER IS PERFECT. She is so well-made.
I started playing this game when Lulu was revealed, and she is what kept me interested for the next few weeks -- the thought that Lulu would be free and I would get to play her and find out if I liked her as much as I did from the patch preview was a huge motivating factor. Then when I played Lulu, I played her all week because I found she even exceeded my deliciously high expectations. I rushed to level 20 so I could spend my IP on support runes, then ground for more IP to buy her with a week later and never looked back. tl;dr: Lulu is a great champion, I don't know anyone who has been disappointed by her, so when you get the chance to buy her, you should totally do so and invest a little time into learning her. Remember to spam /laugh! ♥
The nice thing about Lulu is that she's versatile, and although Riot is attempting to shoehorn her into support, you don't need to learn her as a support. You could just play her top or even mid, and then when you have a grasp on the champion's capabilities you could learn support with her (she's kinda a unique support in some respects, but I learned a lot about teamfighting as a support from playing a lot of Lulu, because that's where she truly excels). Or you could just learn her support then play top/mid/jungle/whatever when you feel confident. :D