There are different tiers in the class points menu, top, middle, bottom. Top is firepower focussed, middle health regen and bottom anomaly focussed (basically the skills you use like earthquake). Middle is pointless since top and bottom can restore your health anyway. Then you need to look at your armour to see whether it is further enhancing your chosen build - for anomaly I look for anomaly boost, cooldown reduction and skill leach.
All devastator builds other than anomaly hit a wall at about WT8 where you just get beaten down by the AI.