Chicken on a Brinkmann Smoker N Grill
Sounds like you've may have two issues. Too much wood and incorrect expectations.

First it sounds like you've "oversmoked" your chicken. Depending on what kind of wood you use too won't need much for chicken (remember it's a lightly flavored meat.) try less wood next time.

Second that "ideal"temperature is great off you want pulled chicken but it will not do god things to the skin. Try either smoking at a higher temp for a shorter time, discarding the skin or finishing it on a grill.

Lastly if your meat had a bitter flavor it could be that you had live flames rather than embers as you smoked. Remember that you want to avoid flareups as much as possible.