JUST FORGET I EVEN SAID A THING. You people cant understand what an idea is apparently.
So. After playing him for about a 2 solid weeks on PBE and buying him on release yesterday, I think I have figured out a good AD Thresh build/ plyastyle.
You cant get around how Thresh is support so direct combat isnt the best idea, your best bet is to poke between farms so you can benefit from your Q passive but still inflict damage. Mainly, killing caster minions first then waiting for your Q....after waiting poke, and after that finish the melee minions. It works even better if theres a siege minion. This cycle and repetitive form of poking iv found works with him but is very dependent on how your runes and masteries are set up. I use my ADC Runes but Hybrid masteries with a salt of tankiness from both. So I have good armor early on (15 Armor from Runes and 5 From masteries) and high Autoattack damage early on. Leveling my Q and E first. Usually maxing Q before E and only putting one point in my shield until iv maxed them both. Thresh can win very quickly in a 1v1 engage if the enemy has been poked enough but on-hit effects are almost madatory in his AD build. Iv also found that so is Marumana.
Overall, the best items iv found so far is below:
-Marumana(Must have on him if solo top)
-Swifty Boots/CDR Boots one or other with Alactricity enhancement.
-Thornmail(Maybe, still working on Thornmail)
-Guinsoos Rageblade(Maybe, still working on this)
-Warmog/Spirit Visage Combo(Maybe both maybe not, just depends)
-Wits End/Malady/Iceborn(Any of these on-hits can work)
Keep in mind that all if this is still being worked on and I still only have a subtle clue as to what is going to work best on him. Its actually very challenging building him AD since he is so much utility.