It would be a very big punt/risk just walking away from Fox. You would want to do a power of research beforehand in what other options are out there, and that will take sometime.
Especially if you going to try setup some FFA TV, Netflix-style type service. Maybe I've been living under a rock, but I'd never heard of that idea. Kind of like it. Any other country doing that currently?
$13.99/month for a 24 hour football station. I presume you'd have other leagues showing, not just the A League.
But man you would need to do your homework first. You would need what 200,000-500,000 subscribers minimum?? Australia/NZ big a enough market for that?