Mercy Stroke Improvement.

I believe Mercy Stroke one of the good cross abilities that can be used, out of GCD, 200 potency, doesn't break your combos and heals you if you were lucky to land it correctly.

But, I believe it would be more beneficial to its users if the heals was somehow much more than a lucky strike in order to get its full effects.
So, as an improvement, I think Mercy Stroke would applies an effect that would guarantee its user the heal if the target dies within 3/5 sec of its application, in that way this ability would be really helpful in many situation, especially tanks when it comes to handling adds or so.

I think that's a good improvement to the ability. I can't think of any way it would be misused. In a raid situation it wouldn't make a difference since killing the boss = done. It'd make the skill even more attractive to monks and dragoons too than it already is.

it's supposed to be a solo option for self healing though. else it would just be an other "hit when hp is below 20%" move

You'd still want to time it to make sure you can get the heal by killing the mob fast enough but it gives a little leverage instead of having to be the killing blow because we all know how unreliable that is.

Plus a small extra would be that possibly multiple people could benefit from the heal in this way.

I can't decide how I feel about it. Either way in endgame Mercy Stroke will RARELY save you from anything. It's worth about 1 Physik/Cure1 on a WAR. The only time I have ever used it that had a marginal effect was finishing off one of the Gusts of Merycidia in T13 while tanking the Sin. Got a 2k heal while I was taking heavy damage, but it didn't really affect much at all, I probably ended up just getting overhealed.

I think a 2 second window wouldn't change much and would keep it in line. The heal component of Mercy stroke is so next to useless outside of a solo situation (and even that would be rare that it would mean the difference between life and death) that I don't think it matters. What I'd rather see is the CD get reduced or the potency increased. Its a much more valuable dps skill than a healing skill.

I like the idea of increasing Mercy Stroke's window to heal, because it would make it more valuable as a cross-class skill. Having it trigger for the MT, OT, & Melee DPS all at once improves the odds of the heal mattering to at least one of them. I wouldn't be surprised to see raiders (or 8 WAR for-fun groups) planning for group MS heals during add phases. I don't think it would address the real weakness of the ability, though.

In endgame content, I can trigger MS on adds ~40-50% of the time when I know a fight, but I find it rarely makes a difference when healers can't plan around the extra healing. The uncontrollable timing of the heal bothers me much more than its tiny window to connect. It usually triggers when I'm above 80% hp, but when my health is low enough that the healing from MS would actually make a difference, healers are already mid-cast on a single target cure, so MS becomes redundant when the Physick or Cure connects.