Sky need to work through the numbers to see what is workable, but I would be aiming for something like:
1. New Sport Bundle (equivalent of starter + Sky Sport + MySky) for $49.99/month 12 month contract (the same price they charge for Sky Sport NOW if you take the 'no contract' option).
2. New Movies + SOHO bundle that can be added to the Sport bundle for $20/month
3. Offer other bundles (like Sky Entertainment) for cheaper than the stand alone price if they add it to existing packages.
I reckon a lot of people would be happy to add (2) to (1) at that price point and have a lot of entertainment (something for everyone in the family) for $69.99 per month.
They could use the same thinking to offer other bundles at attractive offerings for the many customers who do not want sport too.
What they need to do in principle is simple. It's just getting the numbers right so Sky can still make a reasonable profit while satellite customers don't feel like they are being taken for a ride.