The idea is to get out of stun faster than Terran can attack if you're under the effect of his slow (+33% attack interval inflicted by Grasping Roots). Weapons with a 2.6 second attack interval will get away in time, however weapons with a 3.0 second interval will not without the use of interval reduction bonuses. Therefore, it is only safe to use Cloudburst Staff while using Surge I or Surge II at this point of progression.
The safest spell to use while maintaining a decent adjusted clear time is likely the 20k-accuracy Gust, with a wand and a shield equipped.
Worth noting that using Cloudburst Staff, even with Surge I or Surge II, will likely far outpace any other spell/weapon combo. However, be aware that this will cost a lot of runes, and running out of them will put you in danger of dying. Otto or Elder Crown in the passive slot will avoid the need to spend Air Runes on Surge Auroras, making this particular method effectively foolproof.
Any setup you use needs to be checked with the Combat Simulator to be sure of its efficacy for you.
Check if you can idle the dungeon with the Combat Simulator. You can get away from the stun of some creatures in time, so it's hard to use Can I Idle correctly in this case.