How much of a role does the type of hardware used to implement the building blocks (like qubits, the circuits, the communication channels,quantum RAM etc.) have to play when designing the architecture for a full scale quantum computer? 

My own thoughts on the matter: Architecture should not depend on the way the hardware is realised. Because if it did, then every time someone came up with a novel design for the hardware, it would require rethinking the architecture - not a bad idea if you are looking to improve your architecture but that rethinking should be born out of a desire to improve the computer in general and not simply accommodate some new RAM implementation.