My highest hopes are for a knock-your-socks-off new NX, hopefully in the next calendar year. I've been following the Sienna development for a while, and that had been pushed back multiple times, and they're finally starting to ship (I think on net, it's been about at least a 21 month delay). Covid has not helped this at all.
But I think a lot of this has to do with shifts in powertrain development. So many competitors have been going turbo4s, and while the NX adopted one, I don't feel like Toyota's heart is really in that direction. They've had an awesome V6 for a long time, and the best hybrid implementation too. But I still don't think they've found the right new luxury powertrain solution (post V6), particularly for SUVs. For me, the problem with the NA4cyl+hybrid has been the noise. It seems less noticeable on the ES/Camry, but when you get to the Venza/Sienna size, it just gets really loud on acceleration. Now the RAV4 Prime seems to address this, but battery availability is already a limit there, not to mention spreading adoption to a Lexus. But I think these basic powertrain concerns (and combined with Covid) have put development cycles on a very long delay.
So, if somehow, Toyota/Lexus could come up with a turbo4/hybrid implementation that meets their durability standards, I could see that as a possible ground-breaker. And so I'm hoping the forthcoming NX may just have that (and here, I fully agree that it would really help if a few cracks in Lexus's secretiveness would help!) ....
In the meantime, if you can put up with the noise on acceleration, and given that you've had a 2000 RX for a long while, I'd say check out the new Venza. It doesn't have real leather, but I don't think the Softex / NuLuxe is too bad (particularly when combined with ventilated seats).