I think that your slow page load times are due to too many requests aka ads. You should reduce the number of them and you might host them on your servers and that will help you with this issue. I use this theme for many adult sites and I can assure you that it is not the cause of the problem.
You definitely have lots of work to be done. You do not change the titles, they are copied so there is very little or no uniqueness on it, so Google might not give you any good rankings. Also, it looks a general tube, you should focus on a one niche and it will be easier to get traffic and earn some money as there is less competition.
General Tube Site Vs. Adult Niche Site: Which Is Better And Why?