Shoalwater 21' Cat

So, I'm new to running a cat style boat and curious what I'll come across here. I've got an ETec 200 HO on my 21' Cat. Had a little trouble getting up this winter in Mansfield this winter in about a foot of water and didn't pay a lot of mind to it. This weekend I took a couple of soldiers fishing for Warriors Weekend in POC and boat struggled to get up in 18" of water with four men on the boat. Jack plate set at 3 with motor tilted down. Other than shallowish water issues and builder, I've been happy with the boat so far. Curious what others with same rig can "easily" jump up in, and what, if anything they're doing different.