I do not think we have any precedent for a skill-specific aftercast delay. In fact, Nirvanna's work around for that was to give global aftercast delay but impose a cool down on specific skills to compensate for it.
Thing is, his headgear ideas are class specific. Imperial isn't. If it actually does give global aftercast delay (2 seconds! lol), you'll end up buffing other classes (including DB RK and the dreaded PVM Genetic) more.
In fact, for DB RK, it would replace the entire storm stone + peuz set which requires a full gear setup + skill spam + temp boots swapping to keep the 90%. With the imperial setup, it will be 90% at all times for only 1 accessory and 1 mid-headgear.
I can appreciate wanting to buff your preferred class, but do consider what impact it can have.
Though all of this is moot, probably, since imperial glove won't have the aftercast delay the same way sapphire wrist didn't have the cast time for acid bomb.
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On the topic of slots, my opinion (for all 0.02 usd it's worth) is that it should be in the right(window) slot so as to avoid the hassle of accessory swapping manually from the window and to stay in congruence with the other "one only" accessories.
Edited by mildcontempt, 14 March 2018 - 07:46 AM.