paddlers in catboats
A little story... About 10 yrs ago I was up front in a cataboat, one of two paddlers helping the oarsman run the narrowest chute on the Rogue at Rainey Falls. I had paddle in hand, legs braced against cat tube, feet planted well. Although I was well-braced for hits from several directions, I realized too late that I had nothing to keep me from falling forward through the middle (in front of the floor, between the tubes). In a raft it wouldn't have been a problem. As it was, I spent several long seconds under the catboat in a very shallow section of the chute. Scary.
So, be careful about posting paddlers up front on the catboat. If they are just passengers, they can grab handles or straps or whatever to stop a fall. But if they have paddles in their hands, while the tubes stop them from falling outward, but there is no floor/front tube to stop a fall into the middle front like there would be in a raft.