taking into account master primarily, I think you missed mentioning some of the more important points for front-line survivability on pet based jobs.

VIT: DRG > BST / PUP > SMN
DRG: 2nd highest in game
BST, PUP: 3rd
SMN: 5th (last)

HP: DRG / BST > PUP > SMN
somewhere along these lines anyway.

Evasion skill: PUP> BST > DRG> SMN
PUP: B BST: C DRG: C- SMN: E

the rest have secondary defensive skills as well.
All 3 have Parry, PUP has Guard and BST has Shield, even if at E rank.

Traits
DRG has crit def bonus
BST has killer effects (yes it counts especially if you're being targeted, also enhanced by Gausape)
PUP has eva bonus 4 (+48 eva, 2nd highest in game) and crit def bonus

Defensive/Curative Abilities
DRG: Healing Breath, Restoring Breath
BST: none
PUP: Cures from automaton, Role-Reversal
SMN: 3 healing pacts, a bunch of defense pacts scattered across avatars.

Hate-control abilities:
DRG: high jump, super jump
BST: Snarl
PUP: Ventriloquy

Armor
DRG can wear heavy armor not just for melee stats, but also better def.
BST has access to some of them
PUP is mostly cloth and leather class, but can fall back upon its much higher evasion.

so in terms of front-line survivability.. SMN will no doubt end up at the bottom of the 4. maybe you'll only take dmg from AoEs, but that is more than enough to kill you, not to mention the fact that an increasing number of NMs have normal attacks that are AoE already.