More evenly, taking into account overheads and with a long transition period. If the OF continue to hoover up most of the cash, including CL riches, then the "diddy" teams will become even more "diddy". The OF will win most of the trophies, collect all the prize money and buy the best players from the opposition.
In cup games the gate money is shared. There's no reason why the SPFL couldnt collect ticket money and spread it around more evenly. After all the games are authorised by them. Over time the finances would settle down and clubs would be able to pay players a decent, affordable and sustainable salary. The top paid guys would be fazed out.
Best of all Celtic wouldn't have the financial advantage they enjoy now. They'd also be stuck with an oversized, delapidated stadium as their crowds would take a nose dive like they did when we were in the lower reaches.
Its not perfect but I cant see any other way to save the game in Scotland and Id expect other countries to follow.