I look at the stats during a fight, the amount of damage we are doing, the damage we are taking.
Then I review the HP of individual players, how fast people were dropping.
So, after reviewing the data, is very clear, players need to work on HP, protection (higher lvl armor) and those that are dps, the amount of damage they can provide.
Then we've got the whole healing problem.
The majority of the guild wants better gear, they want a crack at Kara and deck out their charactor with epics.