On the one hand, their own class would be nice, then they could be regularly run, but on the other hand not everybody might have a sports car with a podded chassis laying around. I'd hate to see anybody feel compelled to buy yet another car just to have something to run. That's the plus of leaving them combined.
2 cents from a temporarily out-of-touch racer: Although the rules would spec a podded chassis, I see no reason why a racer could not race with an "un-podded" chassis if that was his only option. It would definitely NOT be an advantage. Might even create a challenge for some? Another option along the lines of how NASTE has always dealt with "rule infractions" could be implemented. Cars that do not fully "conform" to the rules are considered "non-compliant". As with the new racer "magnet rule", non-compliant cars could compete but would be officially scored as N/C. They would receive no official credit for their finish position or points in the case of the championship. If they were to win a race with a non-compliant car, that car at that point could be banned. We've had this system in place and I have used it a few times. It is not hard to implement.