When you use Velocity points to fly to/from Europe, your main options are Singapore Airlines, Qatar Airways, and Etihad (for some routes you could also go via USA on United). The number of points required is the same (139,000), but the carrier charges are very different.
500k Velocity Points is sufficient for round trip economy class but for business, its a stretch. Looking at upgrade options, there aren't really any because every option of getting to London involves a partner airline other than Virgin Australia meaning you can't use your Velocity points to get an upgrade.
Unlike Flying Club Miles, Virgin Points will never expire. This means you have as much time as you need to redeem your Virgin Points, which have exactly the same value as miles. So no matter what life throws at you, your points are yours to use now or in the future.
An off-peak economy class ticket between the East Coast and Italy costs just 24,000 Virgin points round-trip. Meanwhile, a flight from the West Coast will cost 30,000 miles round-trip. Peak flights are still reasonable at 44,000 and 50,000 points, respectively.