I don't mean to be the bearer of bad news.
But when it comes to RPM, a lot of the variables involved are not exactly under your control.
For instance, if you started out in a certain niche and has a fairly low RPM, you're pretty much stuck.
Unless of course, you're going to be focusing your content on higher RPM niches.
Another factor that you can control is the geographic location of your traffic.
As you probably already know, traffic from tier one countries like the United States, Canada, and Western Europe, are worth more when it comes to advertisers than traffic from elsewhere.
You mentioned that you are in the entertainment niche.
This is a very broad niche and depending on which type of entertainment the RPM is fairly weak.
You're in a tough spot here.
You're already getting 2000 daily traffic and can you really afford to pivot your site to a more lucrative sub niche within the greater entertainment niche.
Another approach you could take is to maximize the amount of page views you get for every visitor.
I'm talking primarily in the context of display advertising like AdSense.
If you were to milk as many pageviews from every single flesh and blood human visitor your website gets you may get more clicks and this can offset the low RPM.