Maybe i haven’t discovered how to but as far as i cant tell, once you put a rune or gem into a weapon slot, you cant overwrite it with a different one.
I would really like to be able to slowly fine-tune my weapon with different gems and runes. I am fine with enchantments being a permanent undo-able effect, but it feels a bit off for me when the same rules apply to runes and gems.
I agree we should be able to overwrite runes and gems .
Yep, with only the gem being lost instead of destroying the gear item. Feels like a proper in between solution 
Yeah. I made the error of putting a diamond on my weapon without knowing exactly how HORRIBLY PUNITIVE it is when you die, because well there’s no actual number to reference. Now my best weapon is useless. If I kill 10 enemies and die, it brings me back to square one basically. Nice.