Just for fun, the EUP and network management policy is here: »
www.centurylink.com/Page ··· agement/I see that in areas where congestion is identified (that's probably you) they're going to do "a variety of things" to help improve the experience for everybody, and they may even stop adding new customers to a local system, even if there are physical ports available, so that's nice.
They do say they don't block or slow down torrents specifically, so what's likely happening is they're throttling your entire line, and it's probably not because you torrent, but because you're on a system that (for whatever reason) experiences congestion.
You could try using a VPN service to see if having your traffic takes a different physical route on the Internet helps, it'll probably add a little to your overall ping time, but it may be more consistent, especially if some games or game services have high ping but some don't (Blizzard vs. Sony Online, that kind of thing.)
Otherwise, I personally feel like the service I get has been fine, but I'm also That Guy(TM) who can get the cableco, I could get 107/5 from my local cableco, but my local cableco has had plenty of opportunities to prove that they can run a reasonable network, even by CATV standards, and they can't.
Have you found out from your modem and/or from CL what kind of system you're on? They run various things in various places and deployments (even a little today) vary based on if you're in a Qwest/Embarq/CenturyTel area.
This may not help much, but you can also ask CL what options are available in your area, in the region, and on your specific system, for getting more performance. If you have a VDSL2 connection and/or you're on an extremely recently upgraded ADSL2+ system (or one of the systems Embarq installed for ADSL2+) you may be able to get a bonded line, or you may be able to have two independent lines installed, one for your general use and one for gaming.
(My system is "full" -- no word if this is physical ports or just the carrying capacity of the T1s feeding it, but I can't get CL to sell me such a second line.)
Another possibility, and this is more about just talking about what you "could technically do" is that CL may sell you ISDN or a T1. ISDN is extremely slow, like 128 kilobit/second, and T1 isn't much better at 1.544 megabits per second, but you'd be on a dedicated line to the CO, where there's likely a lot of available throughput.
Of course, that's the "few hundred dollars per month" solution, it may be faster than trying to get a cableco to build out, or encouraging a CLEC or a WISP to build.