It could either be an individual holder with 1 billion AMP to propose the idea OR if the AMP community wanted to pool tokens together to vote on ideas then Flexa could make the threshold higher in order for it to reach the proposal stage. This could be active for a period of 1-2 weeks to reach the new idea voting threshold. Then if it is successful it will move onto the final vote for proposal where the 5 billion AMP must be achieved for success. I believe this would further enhance the governance role that the community holds and would enable a wider variety of ideas to be discussed and voted on.