I'm not sure if the IPL has the crowd catch prize challenge that PSL has. The one where there is a certain amount of money divided up by all the people who catch a six in the crowd and each person gets a share of that money. If the IPL doesn't have that, they could implement it as it gets the crowd involved.
IPL has this cap business, where the highest run scorer and wicket taker wears a different color hat, PSL could implement that if they don't already. I don't watch a lot of PSL and IPL so forgive me if these ideas are already implemented etc.