Recommended Thickness of Mass and other questions

So I'm just about ready to start building my new system. Just a quick over view before the questions. I live in northern New Jersey my home is approx. 1200 sqft with an open concept and I plan to have my rocket mass heater as my only source of heat for the winter. I am using an 8 inch system that I am going to get from Dragon Heaters. I am going to cover the unit with a perlite/clay slip mix about 8" underneath and about 8-12" around. The is all going to be incased with cinder blocks to form the outer walls. Instead of using a standard barrel for the bell I am going to be using 24" x 24" chimney flue liners, I am going to be lining it with Inswool Ceramic Fiber Blanket and using Rigidizer to harden the material and increase its life expectance. This should keep the temperature fluctuations down and prevent cracking of the chimney flue liners. I am going to be topping it with a slab of soapstone (unless someone has a better, or cheaper, idea). I am then going to be using 55 gallon drums as half barrels in my bench to use as my very large second bell. I am able to fit 9 half barrels total with the size of bench I am building with a total of 2 90 degree turns. At the end of the system I will be using 8" piping to connect to my existing 18' tall chimney. The entire system is going to be lifted up off the floor by placing brick in rows going from front to back with 2' x 2' pavers placed on top that I will be sealing together with mortar to make it air tight. There will also be a 4" gap around the entire system to allow for air flow. I live on a boulder with no clay soil or any immediate access to clay soil so instead of COB I am going to be using concrete for my mass. I am also going to be running a water line through my mass that will be used for an aquaponics systems that will be on the other side of the wall. The plan is to circulate water from the fish tanks through the line to keep the water temperature up during winter. At one end of the system I am going to have a chaise lounger that will have a half barrel underneath but not as part of the system. It will be used to store wood and will hopefully help dry it out a little extra from the heat of the mass. I am then going to cover the front of the system and the clay flue liners with stacked stone to improve the aesthetics of the system and will be using futon mattresses for cushioning. The back rest will be wood boards that will have a cavity inside (I am going to make the backrest thick) that will be covered with a water proof liner and used to house some indoor plants in a wicking bed system.

Ok so that's the system. Now the questions:

From the half barrels to the exterior of the system how thick should the mass be, both for the top and front?

Will there be enough length of travel for the heated air before exiting the system? I know this is something that I have to actually trial but just wondering if there was a quick answer like "it should be ok" or "that's not nearly enough"

Would the water line end of syphoning off too much heat taking away from the main living space?

Do I have a thick enough layer of perlite between the system and the outer concrete walls?

I am planning to have a 2" gap between the heat riser and the soapstone top is this ok or should I increase it?

Should I add more insulation to the heat riser to reduce the space between the heat riser and the inside wall (of the clay flue liner with the ceramic blanket)?

Should I make the soapstone removeable to service the unit?

Any other comments about the system are VERY welcome.

I am planning to start building mid October so I still have some time to make adjustments.

Anyone please? I can really use some advise on this.

wish i could help you but im a newbie too. someone will chime in on your questions. if you could draw up your plans, and scan them to post, it mite help.

Sounds like a highly customized design with several experimental aspects that go beyond the standard Ianto Evans RMH. Perhaps check in with the "stovers" over at:

http://donkey32.proboards.com/board/3/rocket-stoves-heating

Mark got a reply there.

Adding layout plan. It uses 12 halves but they are cut so in terms of volume it is the equivalent of 9 halves.