Not GP, but BMAD has several interview techniques in its brainstorming skill. You can invoke it with /bmad-brainstorming, briefly explain the topic you want to

Not GP, but BMAD has several interview techniques in its brainstorming skill. You can invoke it with /bmad-brainstorming, briefly explain the topic you want to explore, then when it asks you to if you want to select a technique, pick something like "question storming". I've had positive experience with this (with Opus 4.7).