Car Data - I love it, more the merrier. I think it's quite cool that the team can analyze tiny factors and adjust their strategy accordingly.
Radios - Absolutely keep them. As much for the teams, but also to hear the dispair of Massa in the rain
Refuelling - Bring it back, but do it with less people as it's been said before. I'd be happy with 15sec pit stops and gravity fed fuel done by linebackers.
Tires - Let them use whatever they want whenever they want. Ban the silly stripes and let us all (and their competitors) guess which compound they are using.
Tire Warmers - Ban them. Let's see more talent.
Blue Flags - Just a hint to look in your mirrors...no rule to move over.
Aero - Massive re-think to get the wash down to the size of a dishwasher, not a semi-truck.