I'm against of forced discount of already emitted coins because this destroys trust to development team. Voluntary donations is the only fair way to do this.
I proposed the discount/exchange but I have revised my position and I'm now against it as well, because it is too confusing and some people feel like their coins are being taken away. Whatever other merits there might be, that's too high a price to pay.
Another solution is to temporarily reduce emissions until the new curve is reached. This can probably be done gradually over a period of a month or two. Maybe it isn't quite as "fair" (tough word to define) as everyone giving back their coins, but from the point of view of anyone mining after the new curve is reached, it is pretty much the same (no "extra" coins will have been given out before they joined). I am in favor of either this or the crowdfunding approach.
I'm in favor of the 21 curve. I suggest this be done by leaving the formula alone and changing the block target back to two minutes. The original premise for one minute was to help solo mining. Solo mining is already difficult and new miners are complaining that they often don't get anything, and the coin is only a week old! The increased orphans created by one minute blocks are not a worthwhile trade off.
Failing that I would adjust the formula to the 21 curve.
I will submit my vote to the poll as well as this comment.
I will donate half my coins if the switch is made. It is also conditional on merged mining not being implemented because in that case I will likely sell all my coins and focus my attention elsewhere. Right now that would be about 10k coins. That might be different later.