Thanks for the ideas however I won’t be considering the Musical Fidelity unit as its’ power rating is at 4 ohm, not 8. Keep ‘em coming though if you think of others.
The trouble is jack you are designing for failure.
A bit of history. In the tube days 15 ohm speakers where the norm. That is because tubes are voltage amplifying devices, whereas planar transistors are current amplifying devices.
The problem with planar transistors is their break down voltage. Now 200 watts RMS requires 40 volts RMS at the speaker terminals, but that requires a peak voltage 57 volts. That is going to be right up on the breakdown voltage of output devices.
So, it is much better to design for high current, than high voltage. Now I know the current of four ohm loads blows some and may be a lot of receivers, but that is because the output devices are too small, or not enough of them.
Now you can increase current carrying capacity by adding output devices in parallel. However you can not do this for voltage as all the devices will see the same peak voltage and be prone to breakdown. So by adding devices you increase the chances of failure if you up voltage but reduce chances of failure by lowering impedance and increasing current by add output devices.
My Quad 909s have the output devices tripled so there are six output devices in each channel. Three for the positive deflections and three for the negative, rather than the usual one for each.
For solid state devices voltage kills, due to arcing through the semiconductor material. Current kills due to overheating from the I squared R losses in the devices. The current issue is solvable, but the voltage issue is not.
Next, if you put seven 200 watt amps all channels driven on one box, then the power supply is going to be enormous with a massive heavy and expensive power transformer.
So I really can't warn you enough about how bad your design plan is.
You are favoring domestic/architectural design over sound engineering. That is always the wrong trade off.
There are sound engineering reasons why my power amps are 20 to 40 years old.
I should add, that this really builds the case for active speakers. The amps will fit in the speakers without significantly altering their size. Making active speakers the rule in these days of multichannel audio will greatly increase performance and improve the interior design of listening rooms. In addition amps will be lower power which will up reliability. At least half the amp power and usually more is lost in passive crossovers.