For a long time, I did only heavy compounds, powerlifting style. While my torso and legs were thick, tris were good, but bis especially were lagging. Deads and rows don't do much for my bis or most powerlifters. I have got some good bi growth with some biceps isolation movements last month.
I wholeheartedly agree on alt dumbell curls. This has really helped my bis. Then I do barbell curls with the cable. This seems to work better than barbell curls, probably because of the constant tension and nice negative movement. Then I use a machine curl (nautilus, hammerstrength, etc). On all three exercises, focus and squeeze. You should see some good bi growth that way. I know it's helped me.