PSA if you are first pick support and you aren't gonna play Janna
Ban her. Holy hell ban her. Your teammates will give you the courtesy to decide whether or not you want her banned since you're FP, but for the love of god if you aren't playing her ban her.
Just had someone fp support and NOT ban her. Needless to say his lane lost and Janna became a monster threat via huge teamwide buffs.
Cannot stress this enough. PICK OR BAN HER.