A word of advice to the organisers of this project. I know it's not easy to keep everyone happy, but you can't allow a fear to regulate last minute decisions. You've made your decisions in good faith and reason, and you've communicated those outcomes to your audience, now you need to stick to your guns, come hell or high water.
There is no real substantial evidence that the fears of botnet mining are real. In fact, in the past, botnet operators have been honest about mining. Botnet operators have as much place in the cryptocurrency community as anyone, because they, just like anyone else who mines do the network a service by securing it. The network does not discriminate in this way, and neither should it. Any botnet operator will participate in the cryptocurrency economy if it is worthwhile.
The fact of the matter is this: CPU mining is the only true decentralised way we know of to distribute a coin as fairly as possible because anyone with a CPU can mine, and almost everyone has access to a CPU, whereas not everyone has access to a GPU. Don't screw the people who supported you up to this point and then end up locking them out of participating because of botnet fears (you'll just trade the fear of CPU centralisation for the reality of GPU centralisation). Where have we seen that kind of logic before?
Just my 2¢. No hate required.