I don't think you'd see much benefit from Threadripper then, even when the new one comes out.i do a fai bit of rendering but not majorily high level. i'm trying to future proof as much as possible by getting the best i can so it lasts a while
If you invest in a decent X570 board now with the 3900X then you'll be set for a while, plus should be able to upgrade to a Zen 3 next year as well.