I suppose that it all depends upon the size of the layout, the length of the various track segments (e.g., mainline, reversing section, yard, etc.), and the number of feeders in each track segment.
BMMECNYC, each of your options requires the OP to get under the layout except, possibly, for Option#4. But even under Option #4, the OP will have to install a power routing turnout if the existing turnout is non-power routing and disable the feeders that currently power Ferry Yard. So, in any event, the OP is going to have to get under the layout to do something with the feeders.
In my opinion, your Option #1a is the preferred option and the one that I am suggesting to the OP. Using Option #1a, no gapping is required where the OP has marked “not gaped/short”, nor would there be any need for an additional auto-reverser or even a circuit breaker.
The best long term solution is to match the wiring in Ferry Yard to the mainlines and the diagonal track connecting Reverse Loop 1 to the mainline. Any train exiting Reverse Loop 1 at the bottom of the track diagram will match the polarity inside Reverse Loop 1 to the polarity of the wiring on the diagonal track segment that the train is entering.
Sure, you could extend Reverse Loop 1 by moving the insulated gaps beyond the turnout up onto that diagonal track. That would make Ferry Yard part of Reverse Loop 1. But once you do that, you will need to move the Ferrt Yard feeders from the main bus to the output side of the auto-reverser that controls Reverse Loop 1. And, you would need to remove the current insulated gaps at the tail end of that turnout.
To do this right and permanent, you should simply flip the Ferry Yard feeders to match the polarity of the diagonal track and connecting mainline.
If it’s easier to leave the feeders attached to the Ferry yard rails, swap them below at the bus and get some cheap craft paint at Michaels or AC Moore and paint the red wire black and the black wire red.
I don’t think that analysis paralysis is at play here. The OP has already taken temporary steps to successfully resolve the issue. Now he is looking for a permanent solution that will involve the fewest man hours of labor, while still maintaining the standards that he has set for his wiring protocol.
Currently the Ferry Yard is on a separate Circuit Breaker with a separate Bus just for the yard.
What I was asking was if I extended the reverse loop past the turnout and gapped BOTH the Mainline Track AND the Ferry Yard Track AFTER the turnout would that work without changing the feeders in the ferry yard.
Reverse Loop 1 is approximately 10’ and Reverse Loop 2 about 12’.
I don’t know why you would want to do that. Where you have the gaps now, at the tail end of the turnout, makes the most sense because it keeps the yard outside of the reversing section.
If you eliminate those gaps and place new gaps on the other two ends of the turnout, you may be asking for problems because the turnout now becomes part of the reversing section whereas before that change, the turnout was outside of the reversing section.
But, let’s say that you relocate those gaps anyhow. The Ferry Yard feeders must now match the polarity of the original reversing section because now it is part of the reversing section and, so, the feeders inside Ferry Yard must be connected to the output side of the EB1.
It seems to me that you are reluctant to match the polarity of the yard feeders to the mainline. But, at this point, if all works well since you flipped the wires to the input side of the EB1, why mess with the wiring at all. If it ain’t broke, don’t fix it.
If the ferry yard is on its own circuit breaker, just flip flop the leads feeding in to the circuit breaker and it will match polarity with the rest of the diagonal rack, problem solved. Don’t move the loop gaps.