>Perversely, I would be perfectly fine with you dropping my connections if I try starting 100 parallel downloads or charging me the same whether I download 1GB or 100GB this month, as long as it's a nice flat reliable fee.
I wouldn't. Never interfere with my packets (except dropping when buffers are too full, of course). Throttle me to 1mbps if you need to, but you shouldn't even know how many TCP connections I have open.