I went through a long period using FHG as a curl cream, over a leave-in and under a hard-hold gel. However, I really needed the hard-hold gel on top for this to work, and ultimately I prefer the soft, touchable feel of my hair with CEJ/FHG than FHG + gel.
I use CEJ more as a gelly for frizz control and light hold than as a curl enhancer. I really like it over a curl creme - don't need an extra gel on top, and hair feels very light and not at all producty.
Ultimately, I use CEJ the way some people use FSG: either to replace gel entirely when used over a curl cream, or as a "cushion" product in between a leave-in and a medium hold gel (like FHG). However, I have found CEJ more curl-enhancing than FSG, so that's an added bonus.
I've tried CIAB on one side of my hair and CEJ on the other, and find that I get a little more hold/tighter curl with CEJ, but more shine/definition with CIAB. So CEJ is more my go-to product than CIAB, which I tend to use more as a finisher.
I don't know whether FHG is more curl enhancing than CEJ or not, but FHG has more hold, so that might account for the difference (at least in part). I used CEJ once under a hard-hold gel and my hair was very curly, but tangly. So now I always use it with a leave-in.
Also, make sure you're using enough CEJ - I use 3 pumps for hair that is in between shoulder length and BSL when wet.