My experience leads me to suspect that there is nothing wrong with pleasure or pain...
And that the balance we achieve is through deeply accepting the pleasure and the pain...
The challenge of course, is our attachments... We tend to cling to pleasure (sometimes called craving), and resist/avoid pain (also called aversion).
We can live a life that is full of passion... we just have to be willing to let go
... and incidentally, the clinging tends to take a lot of 'juice' out of the passion
when we relax and let go, it is much more fulfilling
On the other hand... we can also experience pain... and when we let go of our resistance... the suffering is vastly reduced... and we tend to really learn a lot more
Of course this is all a bit easier said than done... and this is just what my experience leads me to suspect...