Hi Tyres. I've been considering those 2 for my new build. Yes you are right, the RTX 2060 is certainly on a par with your old 980Ti but 2 generations on that's to be expected. The 1660Ti is a great card for the price but for not much more you get the possibility (no promises no guarantees

) of ray tracing if you ever did get or find a game you want to play that will have it implemented. However, even without RT the 2060 is still the one with more bang per buck so I would go for that one.
BUT, if you are staying at 2560 X 1440 you have to ask yourself why bother? The 980Ti is more than up to the job as you know and I can't see much performance gain in terms of FPS with ED using the 2060 instead of your 980Ti. The 2060 probably has the edge but I doubt you'd notice any difference going about your ED business putting them side by side with the same rig.
The connundrum I'm having is all about 4K. I have a decent 32" 2K monitor but it's not a gaming one with a very low response time and a high refresh rate such as 144 hz, but it plays ED very well. I play mostly Military/Space Sim/Action/MMO/RTS type games where I'm controlling some sort of vehicle rather than a living being FPS so my monitor copes with all that quite well. Having a G-Sync monitor also helps a lot but they are not cheap.
But if you or I are going to 4K, then a new 4K monitor at least 32" in size is obviously needed (4K any smaller and you'll need a microspcope) AND the RTX 2060 won't be up to the job at high or ultra settings. An RTX 2070 or 2080/2080i-the descendant of your current card will be required. The cost of those 2 will be 5 or 6 times more that just a 2060. For example the Acer Predator XB321HK G-Sync monitor in the UK is around £750 and it's a similar amount for an RTX 2080 and even more for the Ti version.
So the question is for us, is it worth spending something like £1500 to get 125% more pixels pushed around? Or are we happy with how ED looks now?
My other option is to stick with a new RTX 2060 which I know will work great at 2560 X 1440 and get a high end at least 32" or ultra wide gaming monitor (the extra pixels across won't bother the 2060), possibly one of those curved ones. I can't help wondering what my museum piece Commodore 64 playing 1984 Elite would think of it all! Fly safe! o7