I’ll let you read the discussion here instead of further hijacking this.
A couple notes, though:
The DM30ACs were custom designed for LIRR, and had the teething issues representative of this.
My thought was that a four party convention of NJT, LIRR, Amtrak and Metro North could have put out a bid to design a locomotive that works on all four systems. This would replace the DM30ACs and P32AC-DMs, and bring down costs, but it didn’t happen.
The third rail could be extended out from the tunnels, but your point about multiple voltages is very important.
Very good thoughts, I appreciate them!