Thinking of dual speccing, general thoughts and gear tips appreciated

[Isabellé]

Hi! I'm a frost mage on Kazzak, raiding HC with "The Promised Ones" and we just took Curve last weekend.

I fell behind a bit on dc due to inactivity (uni life got in the way) and I really feel behind on certain ST fights, like Taloc and Devourer. So I've been thinking about dualspeccing for the more ST heavy fights. I'm leaning towards Arcane more than Fire (I played Arcane throughout Legion) because I'm already familiar with burn and conserve.
I do still keep high on the damage charts, outdoing our other mage and topping some fights.
With the preamble out of the way, my concise questions are:

* Is my gear compatible with either non-frost specc, is it more compatible with one than the other?
* Assuming I start doing this, which fights should I stick Frost on, and which would you recommend going arcane/fire?
* Is this even something worth doing or am I overthinking this?

I appreciate any advice or just thoughts.

https://worldofwarcraft.com/en-gb/chara ... bell%C3%A9 Here's a link to my armory profile.

With love, from Sweden
Isabellé