At this stage there are no real essential Blue CP. You could put points into Quick Recovery which would be ok for Tanks. You could put points into Blessed but it offers very little return. You could start to put points into damage areas to increase your chance to apply status effects which will be helpful for group content. I’m going for the status effect CP.
10 Piercing → 13 Battle Mastery
40 Eldritch Insight, 40 Tireless Discipline
10 Quick Recovery
40 Hardy, 40 Preparation, 40 Elemental Aegis
50 Duelist’s Rebuff (Slottable), 50 Enduring Resolve (Slottable), 50 Unassailable (Slottable)
50 Bulwark (Slottable)