What i would do is this, once house is up order 12 yards of road crush use that as floor base ..
Then measure inside diamter use a 2x4 on curved part of greenhouse giving you a idea of table height as well as plant height not being restricted to the poly ,, you do not want plants to touch poly
so in a sense tables are about 2 feet away so lets say you make tables 2 feet level off the floor allowing another 12 - 20 " of soil depth i would not go wide
For a total height of 32 " max top of soil
Now you know your table heights now figure out 3 rows allowing walk ways going from one end turning on other end and coming back down other side wall
make center beds little taller i would not go more then 40" this way as plants grow the outside plants are not chocking out inner plants
that is how we did it
Picnic table, bed concept