I’ve talked about this before, but let’s tackle some of these situations:
Close relations: as I’ve discussed here and here, Rickard Karstark is completely full of shit. As GRRM himself says, “The other factor, which you haven’t raised, is degree of kinship. Killing a parent is probably worse than killing a sibling, but either one is a lot worse than killing a distant cousin. Lord Karstark was stretching that aspect of it when he tried to accuse Robb of kinslaying… but of course he was hoping to save his head.” I personally lean more to Karstark at least subconsciously wanting to die via suicide-by-cop, but it’s always good to get validated by Word of Author.
Killing in battle: according to GRRM, “Fighting a battle in which a brother dies might be frowned upon, but killing him with your own hand would be considered far worse.” I would argue that Bloodraven is called a kinslayer throughout Sworn Sword and Mystery Knight, because he organized an ambush and gave very specific orders to kill his half-brother and his half-nephews (as opposed to attacking the Blackfyre vanguard as a unit) – which is strong evidence of intent – and because he took up a bow himself, rather than standing back and giving the order.
Killing in a tourney/duel: Maekar is sometimes called a kinslayer because he definitely struck the killing blow in front of witnesses, and his defense that:
“Some men will say I meant to kill my brother. The gods know it is a lie, but I will hear the whispers till the day I die. And it was my mace that dealt the fatal blow, I have no doubt. The only other foes he faced in the melee were three Kingsguard, whose vows forbade them to do any more than defend themselves. So it was me. Strange to say, I do not recall the blow that broke his skull. Is that a mercy or a curse? Some of both, I think.”
…is hard to assess, given that it’s all about what Maekar’s mindset was.
Giving orders in battle: as GRRM mentions w/r/t to Renly, “another factor might be whether Renly gave any orders in respect to Stannis. Did he command Loras to kill him, or offer a reward to whosoever slew his brother? Did he tell his men to see that his brother was taken alive? Did he not address the issue either way?” And what is it that Renly says before the battle that never was?
“Ser Loras will break them, and after that it will be chaos…when my brother falls, see that no insult is done to his corpse. He is my own blood, I will not have his head paraded about on a spear.”
Yeah, there’s a reason he’s a bad man with good PR.
Unconscious killing: I’ve discussed Stannis here.
GIving orders to an executioner: I’ve looked through various sources, and I haven’t seen an example of kin ordering the execution of kin. We don’t see anyone saying anything in either way about Tywin getting ready to kill Tyrion, but you know what they say about absence of evidence…