I dont see how blms die to butterflies. Even before i super charged my blms gear for vagary i was able to drop them by alternating t2>t3>t2>t3 giving them only enough time for 1-2 swings on me. I keep up stoneskin and blink at all times. With enough FC and -casting gear it takes 1-2sec per buff to assure you dont get wrecked. Unless you're ajaing or killing a butterfly you shouldnt get hit by the elementals at all.
Sticking to the topic though, since my lua has a slot for low tier and high tier but doesnt actually swap i only use one set for all nukes with alternating bodies depending on if im doing a mega boss.
ItemSet 334629
staff: 18int/mnd 19macc/mab +5%mburst dmg
head: 19macc/mab +8%mcrit rate +10%mcrit dmg
hands: 20macc/mab +7%mcrit rate +10%mburst dmg
feet: +18mab/macc +8%mcrit rate +4%mburst dmg
legs+25mab
most of the time depending on situation where mp isnt plentiful (or especially during ajas) i use the blmaf119 body instead.
I tested some t2 nukes vrs t5 nukes on mandies outside of town the only things i changed were dosis on/off and elders grip on/off so 4mab vrs 13mdmg on t2 nukes elders added around 32dmg~ dosis added a straight 51 dmg on the t5 nukes elders added 83~dmg dosis still added 51 dmg. Its worth making mdmg set if you spam t2 or less all the time but most of the time in vagary im using t3-6 and ajas with boil NM being the exception as to not do too much dmg and make it split. Yorcia shouldnt be the bar you set your blm for. A high tier nuke set works fine there too because its just toying with the mobs.