Well, it is evident that in any business that begins it is necessary to invert 100 % of the time, it is a porn or not.

I currently make 300-400 a month. The site is focused exclusively to Spanish speaking visitors (Spanish, Latin american and hispanic USA visitors). The problem is that the Hispanic people are resistent enough to pay with card for Internet. They prefer paying for sms or phone. We are the only ones with a site in this niche (gay pron) destined for Spanish speaking, but it is difficult to make money with the site for this motive.

Besides, it is necessary to add the expense inverted in the servers. The bandwidth is very expensive. And though you make a premium section / pay section (buying feeds like pluginfeeds, etc) the major part of the users they continue consuming big quantities of the bandwidth of the free section.

It is difficult to find an average point to convert better.

Provide the studios with a mechanism for uploading their own content. Further, work directly with the studios on putting their content online. Note, however, that most studios will not even talk to you unless your site is worth their time so be sure that your site is unique and has a lot of quality traffic before even approaching them.
What mechanism? It's not enough to provide a username and password so they can upload videos? Or you mean to create a script for this use?