I truly hope that everything is clear trough the image and that you will have no issues to build your new kitchen.
I tried to use every single step of your space, taking care of moving around 16 people...Regarding the space behind your back, on the table, if you think that is too much space, feel free to put some free standing storage...whatever you want..
Also, there are only 8 seats for counter top seating, placing more seats will waste other spaces...
