The topic of N64 emulation has already been thoroughly investigated, with an effort of roughly a year of trials. Bottlenecks in both the jz4770 SoC and GPU hardware/drivers were located, and possible workarounds theorized. The effect of that work can be seen below:
Any further effort of implementing the workarounds would require at least a year of full time work by two senior MIPS-assembly programmers, with a possible outcome of "Sorry, we exhaused all the options and N64 emulation on jz4770 SoC can't run faster than ~30% of the real hardware.". Which puts pcercuei's cost estimate into perspective.
I am locking this thread now, as I see the topic as exhaused. If anybody has any substantive
input related to the emulation optimization, they are welcome to start a new thread.