Just to throw an idea out there, what about scaling the number of track testing days available to each team based on their WCC position? ie the champions get 0 days, down to the team finishing in 13th getting 12 days. To avoid costs the testing days could be used on the Thursdays before a race (where possible). This way fans could conceivably get even more F1 action for their hard earned money at a race weekend!
The team that starts best, ends best.
I dare say that on balance, that has been the case throughout history on balance regardless of whether testing is allowed or not. Perhaps the only exceptions i can think of recently was in '06 where Renault fell behind Ferrari in the second half after dominating the first, and obviously Red Bull last year as well.
I had a similar thought, along the lines of who is leading the championship getting no testing, with teams immediately below getting maybe 100 miles of testing with teams that havent got any points or at the bottom getting 1000miles of testing. Of course as the season goes on and different teams take the lead they would either have their miles taken away or reduced. Perhaps there could even be some mileage accruement system.
Overall a system along the lines of success ballast we have seen in touring cars.
This would help the teams trying to catch up with the big players during the season. The other thing is the big teams will always find ways to get around testing by forking out lots of money on expensive simulators that the smaller teams probably cant afford.

"I knew I had been beaten by the best driver in the world." Rene Arnoux.