wiring

Solid wire, being much harder to handle and bend and feed through a hole in the table from the track downwards is not ideal. I would use flexible wire for feeders.

On my table, I used solid #12 for the buss wire under the table, but that's because it was just basically a straight line under most of the table, easy access, easy to use a knife to slice off a spot of insulation, and then wrap the flex wire feeder around that and solder.

I am planning on using 14 gauge stranded wire for Feeder and Bus lines. Soldering the feeders to track and using Quick Splice connectors for connection to Bus line.

14g stranded buss and feeders here.

Its right on the compromise line of being large enough yet still tolerable to work with.

The main reason to use stranded wire is because of its surface area.....much more than a solid wire of the same gauge.  The more surface area, the better for a variety of reasons when it comes to your intended use.  Google the two and you will find some excellent articles about the advantages and disadvantages of one over the other.  I used stranded wire over my entire layout both as a "buss" and for drops.  It worked just fine and was very easy to manipulate.

I used 14 gauge stranded for feeders and drops.  The only soldering I do is to connect power drops and auto derailment. to the track.  I use 18 gauge solid for most everything else.  I used 18 gauge stranded crossing the control panel hinges.  I use crimp spade lugs for all interconnects with barrier strips.  I buy 30 position barrier strips and cut to length depending on the application.  The screw connections make easy work for updates and troubleshooting.   I use 18 gauge solid single strand, 2 or 3 wire thermostat wire depending on the application.

Bard: (Google AI)

In low voltage applications (0-25 volts), both stranded and solid wires have their own advantages and disadvantages. Here's a breakdown:

Stranded Wire:

Advantages:

Flexibility: Due to its multiple strands, stranded wire is much more flexible and bendable than solid wire. This makes it easier to route around tight corners and obstacles, ideal for applications requiring movement or vibration.
Resists breakage: Its flexibility also gives it better resistance to fatigue and breakage from repeated bending.
Larger surface area: Stranded wire has a larger surface area than solid wire of the same gauge, which can slightly improve heat dissipation at low voltages.

Disadvantages:

Higher cost: Stranded wire is generally more expensive than solid wire due to the manufacturing process.
Higher resistance: Despite the slight increase in surface area, the overall resistance of stranded wire can be slightly higher than solid wire of the same gauge due to the internal connections between strands. This can cause minor power losses in long runs.
Weaker connections: Individual strands can break loose, leading to weaker connections at terminals and solder points.

Solid Wire:

Advantages:

Lower cost: Solid wire is generally cheaper than stranded wire due to its simpler manufacturing process.
Lower resistance: Solid wire has lower overall resistance than stranded wire of the same gauge, offering less power loss in longer runs.
Stronger connections: Solid wire provides a more secure and reliable connection at terminals and solder points.

Disadvantages:

Less flexible: Solid wire is less bendable than stranded wire, making it more difficult to route in tight spaces or areas with frequent movement.
Prone to breakage: Repeated bending can lead to fractures and breakage in solid wire.
Lower heat dissipation: Solid wire has a smaller surface area, making it less efficient at dissipating heat compared to stranded wire at low voltages.
Choosing the right type:

The best choice between stranded and solid wire depends on your specific application. Here are some factors to consider:

Flexibility: If you need a wire that can bend easily and withstand movement, stranded wire is the better choice.
Cost: If budget is a major concern, solid wire might be more suitable.
Current and voltage: At low voltages (0-25 volts), the slight resistance difference between stranded and solid wires is typically negligible for most applications. However, for longer runs or applications where heat dissipation is crucial, stranded wire might offer a slight advantage.
Connections: If frequent connections and disconnections are expected, solid wire might be a safer choice due to its stronger connection points.

14 ga for bus wire and 16 ga feeders.   22ga is small to go around a layout I would think, I use 22 ga for milliamps for my Ross Switches.

I'm a confirmed lead-head. Very selectively use any type of crimp/mechanical connector. They have their place, but I would need a good reason not to solder other than convenience.