The battery was 3 years old at this point and struggled lasting a day. I decided I'd try to repair it and if I failed, I'd get the Pixel 4a.
Well, I cracked the screen, but instead of packing it up and staying home, I got the screen replacement kit as well. The battery part went great, though there were some small hurdles (I may have stripped a T3 screw), I completed it and reassembled the phone to working order.
I wish the kit came with a small vial of Isopropanol Alcohol. I went to buy some, but they didn't have any over 90% in store (pandemic and all).
Also I'm glad I got the screen kit as well as the original screen replacement pieces from the battery kit because I ended up redoing the adhesive on the screen. Honestly, I could have gone for 2 or 3 more backup screen adhesives.
One thing that wasn't laid out well on the screen repair kit was what to do with the adhesive around the speakers. I cut some small tape strips and tried to make a box, but it was clear that it wasn't thick enough. I shouldn't have taken off the thick foam-tape that was originally there. So now my Pixel 2 is significantly less water-resistant. But hopefully I can still have it last another good year or more.