I’m perhaps in my fourth or fifth iteration of sleeping platform.
First four boards in the middle and quite wide. Great but foot room was limited which is useful for general moving above and setting stuff up.

I tried a 50cm wide rear board which was fine no issues with being too narrow for cut down camping mats. The camping mats were uncomfortable something wider for inflatable mattress was required.

I tried everything on one side but despite working on Mirrors and Herons on a Gull the heeling is alarming.
There have then been various versions cutting the sides down to get a 60cm wide platform slightly off centre.

At night I store the sail and oars on the port side, the platform biased over to this side. This gives foot room at the rear and access to tubs and storage at the front.
I generally set the front platforms up quite quickly and then sitting on the thwart can lie back to read resting on the sleeping bag and sleeping mats bag. In the same position I can cook using a rear board as a table, it has holes to take the stove wind shield.

When sailing the platforms are stored over the rear tank but more recently form an aft seating area great for downwind sailing. More about that to come.

I have one more overnighter with the DCA this season and then may remake from some proper marine ply