I think the next big issue right behind internet caps is the absolutely terrible upload speeds that are offered by ISPs which is the limiting factor behind several services that you've listed.
With my own usage case, throttling usually isn't a problem since I've been using usenet
Also, I see you're in London like me, so Teksavvy and Distributel should be available and are both good options for uncapped internet if you want to switch. CC sells a Teksavvy kit that makes the startup fee more bearable. Also, I should note that I've been getting significantly higher speeds than the 15mbps advertised with Distributel that I'm using now. It's been around 2-2.3MB/s and when during off-peak hours, it sometimes goes up to 3MB/s on usenet.