Hi,
Every existing architecture has its own advantages and disadvantages. When you are choosing among different architectures, you should consider about the following:
1)timing(maximum frequency)
2)area(related to your die size and costs)
3)power
4)the back-end deisgn for a certain architecture
So,I am afraid there is no "best" architecture in ASIC design.It just depends on your spec and requirements
The best architecture is that
that is used in the module library
which is provided by this or that technology.
That modules are specially optimized for speed or power on demand.
And the customer will try a lot of efforts to achieve similar results.