[2.4] CI/ZO Glacial Cascade (Need input)

So I wanted to do a Glacial Cascade CI build. I used another CI build's tree as a frame then branched off in different ways. Have been leveling with freezing pulse so far (currently lvl 58). I've tried to switch my 5L freezing pulse to 5L glacial cascade, but it's never more or even similar damage to freezing pulse. Here is my question...

Is glacial cascade just a lower tier spell or am I doing something wrong?

5L Freezing Pulse: 3,867.3 dps unbuffed
Freezing pulse -> LMP -> Faster casting -> Spell echo -> Added cold

5L Glacial Cascade: 2,826.1 dps unbuffed
Glacial Cascade -> Faster casting -> Spell echo -> Added cold -> Controlled destruction

Current 73pt Skill Tree: (Waiting until 70 to switch to CI)


109pt Skill Tree:


Won't even get into discussion on gear because I mainly want to know if I should just break away from using Glacial cascade at all and look to another spell for maps. I am open to suggestion when it comes to my skill tree or gear I should use.

Feel free to message me in-game @ Chilling
Thanks for any input :)

Glacial cascade hit multiple time the same ennemy per cast (2 or 3) wish means you can double or triple its dps depending on your aoe and placement.