My process is similar, but I recently added a new "critique the plan" feedback loop that is yielding good results. Steps:

1. Spec

2. Plan

3. Read the plan & tell it to fix its bad ideas.

4. (NB) Critique the plan (loop) & write a detailed report

5. Update the plan

6. Review and check the plan

7. Implement plan

Detailed here:

https://x.com/PetrusTheron/status/2016887552163119225

Same. In my experience, the first plan always benefits from being challenged once or twice by claude itself.