I like your adjustments a lot but:
Unsure on this.
100% fine on Barrage Turbine, it should just have a small cooldown, shouldn't consume maneuvers.
Fire Holder and Ice Maker though are meant with a clear idea in mind.
The idea of greatly boosting damage a the cost of something. That something is maneuvers + risk of overload.
Flame Holder I feel it's not that vital (they could transform it into a WSD attachment, with lower potency but no maneuvers erased) but for Ice Maker it's a problem.
There's two things to be said about Ice Maker.
One: it's basically the only way to make magic damage decent, otherwise it's plain broken
Two: it's super annoying to use, even with KKK, only worse without that.
Now if we look at things from this perspective I'd say the major issue here is not that Ice Maker is annoying, but rather that magic damage in general is so broken that you *need* Ice Maker to make it somewhat interesting.
The "best" fix I could imagine for this would be to leave Ice Maker like it is, but tweak magic so that it's not so bad without it.
I mean, if we're talking about hopes&dreams, this is what they should do. Of course they won't lol
Frankly I think they should give Tier V to the RDM hat, Tier VI to the Black and that should be a fix to the heads, not the attachments.
Heads could use a plethora of other adjustments, like remove the dreaded Aspir/Drain from the default AI and bind them behind a specific attachment.
YES I know you can avoid that by using ADD, but ADD is:
1) Annoying
2) Was never meant as a proper way to use the automaton, it's just an "exploit" players found as a countermeasure for the jobs' shortcomings that SE refuses to fix.
One thing I find incredibly annoying is how the WHM pet is WORSE than a bloody trust. Despite the supposed control you have over it, even with excessive stress/focus on the maneuvers and attachments you use, the WHM pet is simply crap.
Or rather it's okaysh if it's just for yourself, it's simply not sustainable for pt healing.
I think this is ***. No way a pet built specifically for the purpose of healing should do worse than a bloody trust. Imho, of course.