Atletico Madrid have already pocketed €31.6 million in the Champions League. Great earnings so far, and considering I find it plausible that they could make the semifinals they could earn a lot more.
It's this kind of consistent revenue that's gonna make the club grow long term and become a financial powerhouse to rival Barca/Madrid for years to come. Other la liga clubs could grow similarly with a combination of: better results+better sponsors+going farther in European and domestic competitions. More exposure to get money and support is actually what is going to balance out la liga, not just shared TV deals in the league itself.