There is plenty of pain in avoiding death, and to realize pleasure one must indeed experience pain, and longing, and loss...
The greatest pleasure comes from surmounting the greatest difficulties. To bury your children, and childrens' children. To know you will outlive your love interests, regardless of your futile attempts to impart your gift. To watch the living world burned to ash and blown away, the stars sundered from their constellations and disappearing into the distance one by one until there is absolutely nothing left in the observable universe except for the darkness, and your mind . And not just to experience these tragedies once, but infinitely many times. And to anticipate the inevitable return of all you loved. To seek and desire ways of passing the times between just a few billion years faster.

Yes, there is great satisfaction and self-import in such an existence.