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Auxiliary power circuit

Practical Motorsport Wiring - Club Level

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I'm wiring a 2001 Mazda Miata engine into a 1990 Miata with an MS3Pro PNP ECU. This is a modified street car. I'm also adding an auxiliary power circuit for some additional accessories. This has left me with a few questions.

I need to power a wideband controller (5A fuse), Driving lights (10A fuse), Small subwoofer (15A fuse), Fuel pump (15A fuse), Upgraded PWM radiator fan (50A Auto-reset circuit breaker), and I want to have an extra relay and fuse for future expansion. I think I can fit the relays, fuses, and a small distribution block in the passenger footwell next to the ECU where they will be covered by a protective plate. The MSD solid state relays I'm using have short circuit protection so there are no fuses on some circuits.

I've attached a diagram of my intended power wiring. My questions are:

1) Does it make sense to pull power from the battery? Should I pull from a place like the alternator or starter which are physically closer than the battery?

2) The MSD 7564 Solid State relay block I plan to use has screw terminals. Will wire ferrules be sufficient to make a reliable connection?

3) Does this strategy make sense as a whole? As I look at the factory wiring I have doubts. The factory battery cables seem to be smaller than the 2AWG cable I plan to use and the main relay is only 80A.

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