OK, so:
- I called Queensland Transport, who put me through to main roads
- I then called main roads back (since the first call got disconnected). They told me to call my local main roads office, as their central number doesn't answer questions about compliance.
- I called the local main roads office. The inspector there told me this was an issue of legislation under the traffic act, and hence I had to call the Police instead.
- I called the police central number; they told me I needed to call the local Police Traffic Branch.
Finally, I spoke to a very nice lad at the traffic branch, and asked him about this question.
He said that the only time you need the reflector is at night, and as such, if you instead have a front and rear taillight, and they're both turned on, then you're compliant. You will not be "pulled over" for not having a reflector on during the daytime when you are perfectly visible.
His thoughts on the tape were that it sounded good - anything that makes you more visible is a bonus - but it wouldn't be any "more compliant" than the light itself.