Well Seph.
Depending on types of games played, I think the 2 things that affect gaming are jitter and latency. Jitter on a FPS is going to have more importance than latency as although low latency beats higher latency, inconsistent latency is a killer. If jitter is fine then low latency is preffered but on some type of games jitter isnt a problem and then only latency matters. Since your VM connection seems to not have much jitter issues (better than the VM average) then that gives you a better experience. I agree BT isnt the best isp out there for base latency, even if you on fast path (as I am) they have some strange routing going on. People in london eg getting routed to sheffield and back before hitting london sites. I believe I get routed up to birmingham before going down to london. Plus there is some places getting that multiple round robin affect on some routers (as I do) which creates a permanent jitter of around 2ms, not big enough to register but is there. (the blue line seen on my BT tbb graphs) such as the one below.
If you asking how to get your BT line back to fast path then I would first suggest geta unlocked hg12 modem on there so you can see whats going on, such as sync speed, snr margin, error rate, interleave depth etc. Without that you operating blind. Get some graphs made over a period of time using one of the hg612 graphing apps, that will then reveal if you have a steady stream of errors or you getitng bursts at certian points of the day, you can also check if you are on a ECI or HG dslam, which can be relevant, eg. using a ECI modem on a ECI dslam reduces the error rate sigificantly over using a HG modem on a ECI dslam which can then be enough to make DLM drop it back to fast path if interleaved.