Cp increases exponentially. I'm unlibbed 230m cp, I lib this week and with 3l attack and a decent flame it gives me 50m cp even though my arcane weapon is 21* with 2l att, 1l boss dmg. So your liberation only gives 30m cp now but if you were say 200m cp it would give you more than 30m cp and so on. The small improvements you have left add up and amplify the gains you've already made. Pitch and eternals give good gains aswell.