Also, I know the OP said they don't like printing papers out, but if you do, get a Brother laser printer. Text and graphics are much clearer on a laser printer vs. an inkjet.
I bought a higher-end (Epson EcoTank ET-2750) inkjet to replace a 10 year old Brother laser printer (OfficeDepot display model to boot) I got on sale. The laser printer was better in every way – I should have just replaced some parts and kept it going.
Since I am the OP, I'll note that while I don't like to print a lot of papers, I do inevitably print important ones. I fully agree on the Brother laser printer (only kind I have used, so not knocking other brands). Even printing in draft mode (saving on ink) is generally more readable than inkjet printing, in my experience.
I'll probably end up getting another iPad, but it has been interesting to see what other people use.
My son has a 6th gen (9.7"), and it seems like it might be a little smaller than I'd like. But, a full-size iPad looks giant after being around his device. I'd love to know what the adults are using for reading.
My wife has an old iPad mini (no idea what year/gen), which I have read some technical documents on. That was sufficient as well, though not quite as good as the larger iPad.
I've never used the larger sized iPad models, so I can't really compare.