While I do like the SilverKris Lounge in SIN, the Gold one is perfectly adequate. There are comfortable seats, you're out of the throngs of people in the terminal, food and drink are available (admittedly the food is not awesome but it does) and you can charge your phone etc
Toilets are in close proximity - probably just as a close as walking one end of a lounge to the other.
Showers - if I really want one then I go to the Transit Lounge and pay for one and take a lot longer than I would with a lounge shower.
I don't see the fault being with VA but rather SQ - they would be the one saying no to allowing access I'd guess (when you compare it to having access to First Lounge with EY in AUH).