Performance wise, per core you're looking at about 16% more performance for the 3600 vs the 2700, not a small amount, plus if you upgrade to a 500 or 600 series motherboard in the future you will have PCIe 4.0 capability, adding another less expensive upgrade option to extend the life of your system. Combine that with the fact the 3600 is less expensive, and that games really don't scale to 8 threads, as you can see in the review linked at the bottom the 3600 trumping the 2700X (the prices are off as that's from last year's launch prices, but the frame rates hold), and it's dead easy choice for the R5 3600.
https://www.techspot.com/review/1871-amd-ryzen-3600/