Your levels are just about OK. The SNR & upstream power are very good. I'd prefer not to be > 6 dBmv downstream power - but the great guru Broadbandings doesn't agree with me so we'll give him the benefit of the doubt.
Please conduct a speed test that onlyuses the VM network, i.e. using
http://www.virginmedia.com/testmyspeed/manual.php. Please ensure when adding up the download speeds that you clearly quote MB/s or confirm that you've done the conversion to Mb/s when giving the aggregated figure.
The outside stuff needs tidying up. Then you might need the forward path attenuator again that the engineer removed! Keep it handy.