I don’t think that Frost tree needs a total redesign, but rather some issues addressed.
- Tree should get some choice nodes, preferably also for different situations like single-target focused choice node between Glacial Spike vs passive boost to Frostbolt / Ice Lance, AoE choice node (like options for different placement of Frozen Orb) and utility choice node (like between Frostbite and Deep Freeze).
- Fractured Frost playstyle still needs changes and improvements like adding more spells to the rotation and restoring synergies with other talents. If that would still not work well enough - it could be just replaced.
- They should also address overpriced (like Wintertide) and undertuned (like Deep Shatter) nodes and Frost’s issue where it both has significant gap between freezable and unfreezable enemies and loses many potential shatter effects against CC immune enemies which can affect its balancing.
Most of these issues were explained with potential solutions offered in this PTR thread - 11.0.5 Frost Mage Feedback And Suggestions