Topics in political institution reform

I think you're on the right track, but asking them why they think STV didn't pass is different from asking them what they personally feel about STV.

We could phrase it like this: Did you vote to change the current electoral system to STV (Single Transferable Vote) in the 2009 provincial referendum? (1) Yes; the electoral system needs to be reformed. (2) No; I prefer the current First-past-the-post system. (3) No; STV is too complicated and confusing. (4)No; STV would have caused too many minority governments. (5) No, due to reasons described in 2,3,4. (6) I didn't vote.

(2) suggests that there is something they like about FPTP. (3) suggests they find STV too confusing and/or did not know enough about it. (4) suggests that STV would cause too much instability. We can add more options.