I like to revisions, but what you're basically building is a 1080p high refresh rate gaming rig. This thing will do that quite comfortably depending on the title, and for some time into the future - it won't really be able to do 1440p, but that's fine, 1080p still looks pretty good and will do so for a while to come (particularly if you're able to hit higher fps and utilize ultra settings). I'd argue that the proper entry card for 1440p currently is the rx5700xt, which is around $400 more (or slightly less) than the 1660 super.

By the looks of things with the range of gear that you've chosen you've been able to keep the price pretty bang on $1500 but now have some better parts in there that will yield a better gaming experience over time than the first iteration (imo anyway).