ignition coil questions

OEM ignition coils are well designed. It is possible to use math to optimize wire sizes, number of turns, and magnetic core material to fit in the package, most likely that was done and verified. Mopar kept with the design specification for decades.

It takes several thousand volts to initiate a spark, once that happens, the spark voltage is about 50V, with a plug gap near 0.030". Designing a coil for extra high initial voltage may result in less spark current due to impedance mismatch.

Like most things, too much someplace, may result in less of something else, in another area.

The Velleman circuit uses resistors to limit the coil current, they are on the circuit board. It is a Kettering style ignition with transistor coil drive. Similar to Mopar box, except designed to interface with standard points.