It would be nice to have blood on bladed murder weapons considering there can be too many options as to which is the actual murder weapon used in the killing
#Blood on sharp murder weapons
sinful berry
tulip thistle
Yes, I'm not sure DNA analysis should be a thing in this game (it's probably one of the bits of tech that is better excluded, like cellphones). But you could get "the lab" to analyse a weapon to find traces of blood, and tell you the blood type. Of course any human blood on a bladed weapon is pretty suspicious...
agile apex
Someone might cut themselves on a knife on accident so it could still work without being a telltale sign someone is a murderer
pastel rose
my trick to the blade kills is looking to see if they have a sword, and if not, guessing 💀
tacit solstice
If a DNA system got implemented, I think it should work different enough from fingerprints so it doesn't feel like its just like a duplicate system with a different asset thrown on top of it.