At 5K cycles my battery was still just above 80% capacity but it was draining when in sleep/powered off.
Bought the replacement battery here, replaced using this guide and everything is fine now! Thanks ifixit community!
Worked like a charm with iFixit replacement screen (and a small pack of snacks found in ifixit box). Touch ID came out pretty easy after heating up the glass just a bit and works without issues after replacement.