#1 Get the rights to MLB
I think MLB is the last piece of content Sirius needs to get the right to. Having MLB on Sirius would be absolutely crushing to XM. It is already bad enough that when XM runs a commercial on television the list of programming logos that are run at the end of the commercials has been reduced to lacrosse, formula-1, and MLB.

#2 Run the Satellite feed on a delay
The only downside to Siriusí service is that when the signal drops you lose that chunk of programming. If the feed was run on a delay your receiver unit could reconnect to the feed where it left off rather than losing that content completely.