Thinking about how to spend them there are 2 important things to look at: 1) Number of miles required 2) Availability

Using Velocity miles:
Etihad
EU - Australia = 139,000 OW (PER 121,000)
Availability is excellent in comparison to most other airlines on this route. Also bear in mind they fly to so many cities in Europe so if there is nothing from LHR for example you may find something from CDG.

Delta
EU-Australia = 127,500 OW
EU-USA = From 49,500 west coast to 71,500 east coast OW
Availability is not great but not terrible.

Hainan
EU-Australia = 139,00 OW (CNS 121,000)
Availability is good but routes are limited.

Virgin atlantic/Australia
EU - Australia = 127,500 OW
EU-USA = From 49,500 west coast to 71,500 east coast OW
Availability not great but not terrible.

Using Kirsflyer miles:

Singapore Airlines
EU - Australia = 105,000 OW (PER and DRW 95,000)
Availability not great at saver level

Star Alliance:
EU - Australia = 105,000 OW
EU-USA = 65,000 OW
Availability can be good as a lot more options



Using the ratio of 1.35:1 actually the miles required is pretty similar. I find EY's award availability to Australia to be great, lots of options and a decent product on the 787s and A380s so I would be inclined to use my velocity points on them. When there was no availability with EY, *A or SQ might have something though. Star alliance availability to USA is usually pretty good but it will cst you a lot more velocity points than sticking with VS/DL.

So I would have some in both but keep most in velocity, but as others have pointed out SQ has a 3 year expiration policy to take into account.