If we're talking about gaming performance, then I'm not sure it would be worth upgrading to a 3600 when paired with a 1660 SUPER. Sure, the 3600 can potentially be faster in CPU-limited scenarios, but most newer games are likely to be more graphics limited with that card. Most reviews testing CPU performance in games are pairing the processor with a much faster card capable of pushing double the frame rates, which makes most games CPU-limited at 1080p. And even there, we're not exactly talking about a huge performance uplift worth upgrading the processor for.
Also, at least at US online stores, 3600 pricing is not great right now, typically being higher than the $200 price the processor launched for a year and a half ago. For most...