looking for new support champ to learn

I've played a lot of support for quite a while i'm not really good at much else, I started playing janna but after a long series of nerfs i can't do well enough in the laning phase to have an impact on the game

I've grinded up 6300 ip and i'm wondering:

1. what is the best 6300 ip support champ (braum, thresh, lulu, nami, zyra, etc.)

2. is there a better overall support champ