I'm sort of debating on a new ad structure.

I've always had 2-3 vertical responsive banners on the right and a 728x90 at the bottom of the page. I changed that bottom ad to a horizontal responsive, and the impression RPM went up by 15%... not bad for a relatively minor change!

Later on, I decided to add a horizontal responsive to the top of the page, too. I hated it, the site is now ad-heavy and it pushes the content almost below the fold! But it didn't seem to have a negative impact on the RPM of the other banners, so it end up just being free money (increasing my monthly revenue by about 50%).

So here's the question.

Do you guys think that I could replace the two vertical responsive banners that are on the right with a single horizontal responsive in the middle of the page, and make the same amount of money (or at least, close to it)?

So the layout would become:

LOGO
************************************
navigation
************************************
[RESPONSIVE HORIZONTAL BANNER]

Lorem ipsum dolor sit amet, consectetur adipiscing elit...

[RESPONSIVE HORIZONTAL BANNER]

sed do eiusmod tempor incididunt ut labore et dolore magna aliqua...

[RESPONSIVE HORIZONTAL BANNER]
************************************
footer navigation

... removing 3 banners, and adding a larger banner in the middle. It would definitely look better, and is definitely more mobile-friendly, which could lead to more clicks and more pages per session. But I'm running in the red as it is, so I can't afford to take too much of a hit.