yeah, the niceness and complacent nature of model training makes it hard to try to nuke any idea from all possible angles, which is what a good VC review does anyway. This a confirmation-bias validation tool!

OP, here are some pointers: prompt the model into the most negative, raunchy and insurmountable as possible personality. Give it examples in the system prompt on how VCs (or your average reddit user...) responds to business ideas, maybe as a different persona, then present negatives and positives from the model at different angles. Wash, rinse, iterate.