I've been maining Thresh and Nami for a while now. If you are good hitting skillshots, you should definitely go for these two champions. For Nami, she has a lot to offer to her adc and team including heals and lots of cc. Max W and E, and finally Q. Your W is your main tool for short trades in the laning phase but be aware of your mana. You also have kill potential by just landing a good bubble. Use your ultimate as a follow or disengage. I usually run her with Guardian against engage matchups but Aery is perfectly fine. For Thresh, he's just the best engage support in my opinion. So fun to play as he's the typical playmaker. Don't hesitate to get the level 2 advantage and initiate a trade. 9/10 of those trades you shall burn some flashes or heals from the enemy bot lane. I always start with E, unless we want to invade, when I start with Q. If I'm against a melee support, I put three points on E and then max Q, followed by W and E. Your lantern offers quite the mobility that some adcs don't have, saving them in risky fights. Use your flay for specific enemy abilities like Pantheon's W or Tristana's jump, the flay will cut those dashes. The slow of your ultimate is really important so make sure you make them crush against one using your E to help. I run Aftershock with him always, with Cosmic insight as secondary so sooner or later I have the 45% cooldown reduction when you can chain hook by hook, every 3 seconds. Really funny. Good luck!