Hi filmackay. good idea. The one thing I would comment on is your position is that HFT basically enjoys two advantages over other investors ie time and cost. Some advantages occur naturally but not two. Remove these advantages and lets all trade on a more equal basis.
Those who use HFT claim removal of their two advantages are the imposition of taxes and contraints that will affect liquidity, but removal only brings us all to a more equal basis as traders.
What may happen, and what the US is heading towards I believe, is a moving of the balance ie some time contraints and some costs but removal of unfair advantages.
Non HFT and HFT traders are all selling and buying the same product. I am not saying every HFT trade is evil just as not every short trade is evil but they do in practice do a lot of damage by targeting 'vunerable' stocks. The contrary arguement is that 'ramping' has the same effect but in practice that is not done by exploiting artifically sanctioned advantages.