Another suggestion to make the battery war worthwhile - longer races!
when I started racing a lot of mod events were only 4 minutes... then they went to 5 minutes as battery (and motor) technology improved... maybe its time for 6 or even 7 minute races ??
One of the reasons I loved running brushless was because of the longer runtimes
I have also heard of a few clubs here in australia trialing 6 minute stock races