When I first got the Catrike the rack wasn't very close to the rear triangle which made it impossible to carry standard panniers. I made a special support for the rear rack which moves the whole thing about 20cm further back and make it possible to carry full panniers.

I can haul 25kg sacks of plaster and cement, they are just laid across the rack so that each end of the bag flops over the rack lowering the CoG and secured with a couple of bungees.

The above image shows how I moved a set of 5 brand new Anolon saucepans. There's also a bunch of stuff in the panniers including a 25cm stock pan.

The photo was taken at night and as well as illustrating the ability of trikes to safely carry implausible loads it shows just how well retro-reflective materials work in making you more visible, particularly the reflective sidewalls of the Schwalbe Marathons and the reflective patches on the Ortlieb panniers at the back. Photographing things with a flash does exaggerate the effect but it works quite well with car headlights.