You can't hold the the class back from growth, I understand your frustration with the cost....but you are going to have that with with anything the guys that can buy the best parts usually win. Evan in the 2.6 class im sure there are some guys in 2.6 that have more money in their trucks than some of the pro street guys.
The open drive line rule was not made to make the puller spend more money but was made to save the puller money by stopping expensive breakdowns. Also this help the promoter to ensure that his pullers will be out night after night to compete and put on a good show! I have heard rumor that the Kentucky 2.6 class is going to allow open rear end to help them from breaking.
If they are going to open drive line that doesn't mean that you have to put and open drive line in you truck to compete just run it the way they are (and I would bet money that Tim and Gambinos could wax the 3.0 trucks night after night) with stock drive line. Or a puller could take steps... charger this year, rear end next year, drop box reverser to follow. Also if this is not the road that some pullers want to take most pro street trucks should be able to run the 2.6 class with minor changes.
I'm not saying this to start a fight, I just want to help promote this awesome motor sport, and bounce ideas off everyone, in hopes that might help out the pullers, promoters and most of all the fans!!