Spectral has overall +59, whereas the respective shields have less def bonus/more def bonus according to the combat triangle (+47 range def only for the elysian/mage shield)
(melee, ranged, mage, tank)
You mean melee, ranged, mage and hybrid right? Spectral has LESS defense bonuses than the melee, ranged and mage shields.
Spectral's special is having a maximum hitpoint increased by +11 though.
And that ^ + overall +5 strength and +10 offensive bonus on all stats (offensive shield has +10 strength and +15 offensive bonus on their style only)
So yeah it's basically good for everything.
I'll compare a DFS to the spectral spirit shield:DFS gives +7 strength bonus for melee only, spectral gives +5 to melee/range/mage. DFS gives equal def bonus as spectral shield. DFS gives no offensive accuracy bonus, whereas spectral gives +10 accuracy bonus for all combat styles. Spectral shield also buffs your max hp permanently while equipped and can be operated for 20% retaliation damage every minute, whereas DFS has it's dragonfire attack that requires to be charged.