I'm sure the 35 f2 will be a fantastic lens. I don't believe that there are enough differences between the two lenses to justify both. If you need WR then get the one that has WR. F1.4 vs F2 is not an argument. Both should be perfectly usable in low light interior situations.
For those of you who like to hang on to every piece of gear for decades, no one is stopping you. Nothing wrong with collecting if it's your thing... I'm sure its tons of fun. It's not my thing, I like to trade up whenever possible if necessary.
I do believe that if you can capture fantastic photos with a camera today, as long as its functional in 30 years, it'll also be great but if it makes sense for whatever reason to trade up, then do so.
I don't find it narrow minded to shoot with a wide selection of focal lengths... (narrow/wide... c'mon, the words are even opposites) you can have your favorite if you want, that's fine. You can shoot with only one if you want, that's fine... I'm not judging you... do your thing and make beautiful photos.