If you compare the ratio of points to ratio of avg damage done vs total wounds, the damage ratio actually comes up slightly less. As vanguard CAN kill him in one turn, but they average less than a kill unless you also stack on WoM.

Morty also shouldn't be near unkillable. If they wanted him to be, he would have had a max damage per phase ability. Morty is super durable, but the auras are where he is gets scary. His bigger issue is being right at that 18W mark, so he can't get obscured, so any DG player vs admech would be best off sticking him behind Dense terrain anyway. Outside of Solar Flare Lucius (which Lucius is an issue anyway), you should be able to soak a lot more damage that way unless they want to lose their ignore AP ability to change it to ignore terrain.

Admech need tweaks, they don't need a full on drowning in nerfs. There are few enough Admech players around as-is.