You mean like this: https://www.wrc.com/en/wrc/news/may-...3--12-12-.html ? And that wasn't even the fuel igniting, just the hot exhaust.
Due to the instant-pull and low gravity it is entirely possible to make it really fast. Adding some throttle-regulated sound is another possibility, it's not like current (turbo) R2 cars are exactly loud, same for most R5s. Range is the most funny argument of all, already now you have 20-30 km stage and then easily 1 hour of waiting. Stage distances between service are usually on the order of 60 km as well.
Seriously you people sound like old grannies arguing how this new internet thing is all wrong. Case in point here "proper rallying" for some people is RWD escort on a gravel stage. That might be fun to watch but it does draw manufacturers money, huge crowds or many new young drivers.
Probably a lot less than you change transmission or engine components. Note that battery degradation affects mostly capacity which does not matter as long as you have enough to finish the stage, while degradation of mechanical parts on normal car directly affects performance.