Vanguards aren't squishy,well Assault isn't atleast,haven't played tactics in a while.
You have alot of survival tools as assault
-Diversion gives you 30% chance to resist everything for 6 seconds(stuns,melee,ranged,tech,force)
-HOT you can get some distance and start kiting melee with ease
-Shield flat 25% DR that also deals 1k dmg to people that attack you while its active
-Adrenal another 25% DR
-Medpack before you go under 30%
-Adrenaline rush,you wont die while this CD is active,30% DR and keeps you just above execute
-AoE stun,if 4 people are on you,just aoe stun and you have stunned their entire team for 3 seconds while you kill your target..
VG is fine....