From all I know, Force Storm and Force Death Field are far more powerfull than crush (in group)
I've got lots of events with many enemy's and 1 use of Force Storm causes (in 1 round) about 80 damage to every enemy (12 enemy's x 80 = LOT)
(Example: Onderon, group of 15 attack me, 1 storm, all dead except 2 (with 12 VP or less )
Also got many events with many enemy's where death field got me from 28 to 280 in 1 attack (lots of damage too)
If you keep casting Force Death Field in a large group you just can't die (even if they damage you 200 per round)
The nice thing of crush is is does a lot of damage even if you don't have the full damage. I've beated many Dark Sith Lords (Sion) by just using Crush (saves) till death, as they are lifted in the air they can't attack and if they land they get a new dose of Crush (defeated Sion by taking less than 100 damage , even a Sith Marauder was harder (escepicially if there were 2, yikes)