I would like to see national lower level racing with tintops. Every nation has those series that run with a hobby budget, very limited modification allowed, speeds might not be so great, but cars usually require good driving skills to keep up the speed.
Also such classes provide very tight groups and close racing, much more enjoyable fighting from position than some ultra fast classes.
We always see big series because just name of such makes a sales, but those lower classes are where you really need to nail your braking and cornering to be at podium, there is no engine power to fix driver errors.