There is a very nice hookah lounge around here (Dream) that has many fruits to pick from. Off the top of my head, I know they have orange, grapefruit, and watermelon bowls. I've tried the orange and it was very, very good with orange/mint mix.
I assume the reason your draw is poor is because you had the stem sticking too far into the fruit, near the foil. Picture a real bowl- the stem is a good 6" or more from the foil, lots of room for airflow. The best idea is to make some sort of stopper (even if its just electrical tape wrapped around and around) so the stem only comes about 1" into the fruit. To do this, however, you'll need a screen of some sort to put over the stem's top (otherwise shisha will just get sucked down it).
It's not the easiest thing to get right, but it's impressive to break out with people over once you have it down.