I think you may be reaching a little bit with a $500M price tag for demolition. I know that a number similar to that ($500 - $700 million) was being thrown around in the recent past but there is absolutely no reason why taking down the stadium should cost anywhere near that amount. I remember a demolition expert being interviewed shortly after that article came out and he said it could be done for $50-100 million. Of course, the actual cost of demolition would remain to be seen. However, the Big O is bleeding money at an alarming pace and we need to do something to stop it. $20 million a year in subsidies to keep it operational is not a small chunk of change. Now we're talking about a new roof (how many times have I heard that one before....) that will cost in excess of $300 million, but will that come with a guarantee that this is (finally) a permanent solution? Or will there be more problems 5,10 and 15 years down the line? As well, the inside of the stadium is outdated and somewhat decrepit. It would cost even more money to re-model the stadium in the hopes of attracting large-scale, international events.
You're right about one thing, the Big O has cost us A LOT of money. That being said, it may be time to cut our losses and walk away. We may not have gotten the best return on our investment, but at least the stadium wasn't a total loss. It has served us well over the years. Like you said, both our city and our province are not rich enough to waste money. That's why I'm suggesting we part with this constant burden, while keeping the iconic tower that we all know and love. Sure, it will cost us a lot of money to demolish it, but it will cost us even more if we keep it. We turned the Forum into a movie theater/shopping mall for God's sake lol, I think we'd survive without the Big O.
Sorry for the long post!