How to balance the bitterness of Habanero peppers?
Capsaicin is an extremely bitter(in addition to spicy) off-white crystalline powder.  The bitterness is also very dependent on the individual.  You'll need to add a lot more sugar or possibly vinegar to offset this.

The flavor of certain fruits play well with chilies including stone fruits and mango. And, anecdotally at least, are know to counteract the bitter effect of the capsaicin.

Or you could use a milder chili.