You will get used to the lid. I prefer it actually - just get into the habit of giving it the "Tupperware" burp.
The "new" tanks - as in since 1989 - fill and empty more quickly. And I rarely see any problem with leaks.
I've used the Super System IV tanks for years - sometimes heavily. I have had one used when I purchased it tank crack after I used it for a while. It was easy to repair with some generic "Crazy" glue. Otherwise the tanks I have had have performed without problems.
I have some Paterson reels of various vintages. I believe you are correct that the more recent ones are made of a more flexible material, which appears less likely to become "brittle" over a long time. That being said, I think all my Paterson reels appear to me to still be fully functional - I just rarely use them.
Almost all of my film is developed in the AP/Arista Premium/Samigon clone reels that are designed to work in the Paterson tanks. They appear to be made of the same material as the more recent Paterson ones. And the wider feed flanges make it far, far easier to load 120 film.