Why do healers feel like they get a punishment for getting better.

with the setting off a trap though you often will just use a pomander to deal with the situation though so that doesn't really shift a healer experience though and does pulling an off type monster really shift things the healer will generate aggro if a dps accidentally pulls it so the tank has to pick it up and you continue spamming heals what does this really change for the healer you might shift a gcd or an ogcd onto the dps?
With this ewer example you see it in card games people will run a worse option because it makes them happy, and sometimes works in their favor but 14 with its lack of customization can't really chase that feeling, unless you play blue mage. What you are saying with unpredictability and "ewer moments" seems more to be wanting more variance in fight design which would require a complete change in fight design, there is an area i think you see that tension and variance but not intentionally which is ba and 24 mans though with how easy those are with the amount of people there will be people making mistakes and they slowly build up those vuln stacks on people making healers suddenly need to work harder. In hard content like 8 man raids and trials though I don't think we can ever have enough variance to get this outcome you seem to want specially with the punishments were given for failing mechanics.
It feels like you're asking for things that this game isn't trying to do.

On Palace and Eureka, I have a feeling that you and I have different reactions to the shifting flow due to changes in situation. For example, even with pomander use being common, you now have three states: before trap, before pomander, after pomander. The fact that this exists at all is the important thing, and does tie into my Ewer anecdote as well. Pomanders are "clutch", which is why you use them in those dangerous situations, and I believe my old FC mate wanted the Ewer to be clutch, as well. It's why newer players tend to hold on to skills like Benediction and Hallowed Ground, after all.

You ask about stray monsters in Eureka, and if it changes anything. My position is that yes it does; but you won't see it in skill use. You have a state where players have everything under control, and other states where things are uncertain. And that needs a degree of unpredictability. You spam heals because you want that stray monster dead and a live tank gives you the best shot at that, as opposed to spam heals because the boss spams tankbusters here and a dead tank means a wipe. Similar situations, but the feelings are different.

Besides, whether or not this game wants to be more dramatic isn't the point. The question posited by the thread creator is "Why do healers feel like they get a punishment for getting better?" My answer is still currently "Because you want dramatic encounters, and the standard 4 and 8 man instances are not interested in drama."