It's not a matter of what you should desire, it's a matter of what you'd desire if you were internally consistent. Theoretically, you could have values that weren't pleasure, such as if you couldn't experience pleasure.
Also, the naturalistic fallacy isn't a fallacy, because "is" and "ought" are bound together.
Why is the internal consistency of my preferences desirable, particularly if it would lead me to prefer something I am rather emphatically against?
Why should the way things are be the way things are?
As per a recent comment this thread is meant to voice contrarian opinions, that is anything this community tends not to agree with. Thus I ask you to post your contrarian views and upvote anything you do not agree with based on personal beliefs. Spam and trolling still needs to be downvoted.