Brushes humm the only reason I went back to electric cars was due to brushless.
Due to brushless the sport has grown considerably in locally areas with lots of nitro racers and nitro only clubs moving to electric and running electric classes.
Electric is as strong as I have seen it in the last 10 years, almost as strong as it was 15 years ago when no one ran nitro at all.
Running one class will not work for a bucket load of reasons; can you imagine having 50 racers plus and possibly 80 at club days not to mention big events; raw power and speed, sure the new timing ESCs are faster in the top end but they still do not have the shear grunt that low turn motors do.
I run a 10.5T and I wont run mod for the following reasons, huge amount of power difference for the first 1-2m out of a corner which is particularly hard on tyres and drive line components which requires many more replacement parts increase cost conserably.
There also needs to be a class to support up coming racers sure everyone can start in novice with a silver car of RTR low powered brushless system if they enjoy the sport they will move up but the step up to mod is just way too far and well beyond
Final note on this topic brushed motors should be flat out band, classes locally still allow them and with the changing regs brushed motors will probably be slightly faster. If brushless motors are banned or brushed motors return I along with probably 50% of the guys I race with will quit overnight and run nitro.