The fines are nothing, and won't stop the fights.
Here's what I'd do if I were the commish. I'd issue orders that each team would forfeit their next 10 games. That's right, forfeit. And if any of the players were seriously injured in the fighting, I'd increase the number of forfeits to 25.
That's right - I'd handle it kinda like when kids misbehave badly. EVERYBODY suffers the penalty REGARDLESS who was at fault.
WELL SAID!!!!