[Si Coe]

When this has been proposed at club level before its generally been considered this way - you can have say 10 min finals and 3 rounds of qualifying, or 5 min finals and 4 rounds. The length of the day, and the time on the track - stays the same.
In nitro the key feature of the longer final is the fuel stop - in effect the race has to be longer than a tanks worth to force you to refuel. Any electric race longer than 5 mins, but not long enough to need a battery change does not have this need, so can really be considered as a conventional final, but over more laps.
In this respect I fail to see the advantage. Few races would end significantly differently after 6, 7, 8 mins than the running order at 5. True there are lots of races with last lap dramatic maneuvers but these are a sprint to the finish and would simply occur after 8 mins not 5.
The only effect is the greater emphasis on reliability and endurance. One of the beautiful features of the modern era is that even at entry level drivers can have cars that can run at full race pace for 5 mins without worry. In the past, having the best cells used to really make a difference, but now it doesn't.

I just figure that really 1/10th offroad is all about sprint racing. Endurance racing is a different concept.