One thing that annoys me with all of them - they were all too cheap to install real test points. Just to save a few pennies! When I see this, all I can think is "where else did they cut corners"?

Out of those choices - the one at Marco looks best. The designer knew enough to put as many high current traces as possible on the *bottom* side of the board where the high current connectors are soldered onto the board. The Marco board appears to be the same as K'sArcade except the Marco board has heat sinks on the two bridges.

The original boards were easily repairable. Did you check the fuse and fuse clips associated with TP4?

Intermittent is often a connector issue. Most probably there is at least one plug in there that needs repinning.
For good info - see here:
https://www.pinwiki.com/wiki/index.php?title=Bally/Stern

For bridge rectifier thickness between GBPC versus KBPC -- it is the specific manufacturer that makes the difference.
For example -
Fairchild / ON-Semiconductor GBPC is 10.97 to 11.23mm thick.
Taiwan Semconductor - GBPC is 10.97 to 11.23mm thick.
MCC GBPC is 7.4 to 8.5mm thick.
Doitec Semiconductor KBPC is 7.2mm to 8mm thick.
EIC Semiconductor KBPC is 7.1 to 7.9mm thick.
Vishay GBPC is 7.4 to 7.9mm thick.

SIC (whoever they are) and Comchip seem to be the only ones that follows the KBPC being thicker than GBPC.
SIC GBPC is 7.5mm to 8.1mm thick.
SIC KBPC is 10.97 to 11.23mm thick.
Comchip GBPC is 7.5 to 8.5mm thick.
Comchip KBPC is 10.77 to 11.23mm thick.

All of the ON-Semi (formerly Fairchild) bridges that I have been getting have been the thicker style.
ON-Semi did what they do best - they hiked the prices for their bridges to the moon and won't budge on pricing. I don't care for Vishay - the leads turn black far too soon.

Just as bad - have seen what has happened to Aavid heat sinks? Bought out by Boyd and prices have quadrupled since January. Looking into getting heat sinks custom made to compete with the 6222BG heat sinks. The heat sinks shown in last photo - too bad they don't publicize the thermal resistance of these. Those work but are actually a hair too big for bridge rectifiers, would have been better at 29x29mm.

CUI has been around for quite awhile - we use their wall warts quite often, they work well.
They're new to heat sinks but they won't make bridge rectifier heat sinks. I know - I asked.