I believe you biggest issue is the return line size. Common sense says otherwise, but the 1/4" vapor line inhibits proper operation of the regulator, causing intermittent problems. If motor is mild, it might better to use 1/4" as supply, up the pressure a bit.

Any EFI's guru's concur?

are just add another 3/8" and forget about it.

Reality check, that half the population is smarter then 50% of the people and it's a constantly contested fact.