We have put together a short survey to capture your feedback in terms of what BT can do when you experience home Wi-Fi issues. We would appreciate it if you could take a couple of minutes to complete a short survey. Read more from here, Fix my home Wi-Fi
There are no 'optimum' settings, if it works you have the correct settings. It wouldn't work at all with incorrect settings.
Select Bitswap 'On' although probably won't make any difference either way, SRA isn't supported on VDSL so irrelevant.