I don't know why a successful club should have to give their earnings to struggling clubs.
They will have no one to play against otherwise.
Yes, the league doesn't have a great deal to distribute until there's a good TV deal, but they could also create at least small distributable pools. I've written before about soft caps (salary and/or points) as a means of allowing teams flexibility and also returning any tax to under-spending teams.
e.g., make the points cap say 68 instead of 70, and charge $10k for the first point over, $20k for the next, then ramp it up so that if a team wanted to blow the points cap apart at great cost, they could. If five teams used 70 points or more, and of those another couple used 2-3 extra, you could generate a few hundred grand to put down to clubs not spending the cap.