A simple way to fix the new design is to move the left vertical ad space to the far right.
This is because the human eye needs a hard left margin to read text - which is why most text is 'ranged left'.
Unfortunately, the current design blurs the left margin with an advertisement that is often moving - which is further compounded by the moving advertisements above it.
In words, the eye cannot 'settle' to get its bearings on the page - its like watching a moving kaleidoscope - which explains much of the negative feedback you are getting.
You should also consider using a smaller, denser, darker type for the body copy - because the big light face is not ideal.
Finally, try to reduce the amount of white space. I know its very fashionable at the moment to have these spaciously airy web pages - but believe me, the only ones who appreciate it are the designers themselves (who love trends) - not the readers who have to scroll through it all.
I have worked in visual design for decades, and for some of the largest corporations on earth - so these suggestions are well founded.
Your advertisers may not like these changes because it makes them slightly less prominent on the page.
But if you stay with the current design, you will lose so many readers over time that the advertisers will leave anyway.
So it's better to bite the bullet now.
Good luck with your deliberations.