Like Marty said, the new iPads are "probably" great. I only say probably because I have not used one. I have owned the original 9.7" Pro with the A9X and the 12.9" Pro 2nd Gen with the A10X.
I did also have a brief week with the 11" Pro 3rd Gen A12X. The biggest differences from the 2017 to the 2018 Pro's were the use of Face ID making things more convenient as I did not need to keep putting my thumb on the screen to verify passwords and the chip. The A12X or maybe the speed of the RAM, I don't know...made browsing in Safari MUCH more comfortable. I can only imagine the additional 2 GB of RAM if we're not talking about the 1 TB edition would help when browsing through multiple tabs and/or app switching like a Pro.
Basically, I'm telling you to get it from somewhere you can return it. I'd also recommend getting a screen protector, but that's up to you obviously. Finally, Incipio (?) made a case that rotated for portrait viewing and held it up at a few different angles. The way the case opened, the front cover (part that touches the screen) never touches the desk/floor/whatever you set it on.
I'm a bit of a speed freak, but I can't help feel as tho you'd be blown away and super happy with the 2020 11". If you feel like you want the 11", then go for that. But just to confuse you, the 11" 2018 did not have the option for "zoomed" view like the 12.9" did. As such, I found reading text more difficult. When comparing two "things" side by side in Safari windows, the 12.9"'s a killer option IMO.
Good luck with your choice!!!
Oh yeah, finally, don't worry about what's on the horizon. Something's always on the horizon. If you wait, you get the new hotness. If you jump now, you can enjoy what you wanted/needed now, read about the new hotness, and wait for the model AFTER the new hotness to upgrade.
Something's always coming out, but if you can stay "behind the curve" and be content about your choice, the new mini-led A14X that "runs circles" around the 2020 that you bought doesn't have to "bug" you because it's going to be the "old model" when you upgrade in 2022 or whatever. Make sense?