I'm all about creativity .... if the fatality is a well done, that give creeps, shivers and has shocking value, I will not worry or care if takes a few more seconds in the screen to happen all it animation sequence.
Baraka Brain Eater and Geras Skinning Alive fatalities are both very good fatalities, that, could suffer if they had reduced their total timing presentation
Anyway, I turned a great fan of Brutalities in MKX, so, I love Fatalities, but I love even more Brutatilies , since many of them are pure homage to old fatalities in the MK franchise/series