I don't know anything about your smoker, but I am going to guess you need to bring your temps up to 225-250 so the cooker will feed more pellets. More pellets = more smoke. Fire control on any cooker is the key to a successful cook. Don't give up on it so soon. Learn to master it.
Also a brisket should take around an hout to an hour and a half per pound. Depending on if you wnat it sliced or shredded.
Good luck and have fun with it.
KCBS CBJ 9831
Large Spicewine, Backwoods Smoker (Party), WSM, Oklahoma Joe's Offset, Wood Fired Oven