You are so very lucky to be able to just use a LI condish!! If your hair looks amazing with just that and you are happy, there's really no need for anything else! But, at the same time, you could always try a sample of some sort of gel if you're curious and feel like experimenting.
I'd stick with cheap ones, like something super inexpensive from the drugstore or a more expensive product sample from Kathymack -- that way, if you don't like it, you won't be wasting money. So, you can satisfy your PJ and not go overboard spending money on hair products.