Correct internal or external coil for pertronix points eliminater

If Pertronix I doesn't control coil current, then a resistor is needed to control coil current.
For an ECU era chrysler the resistor is 0.5 Ohms, and should be used with a factory coil.
Points cars had resistors in the .6-.8 ohm range, and again use with factory coil.

Higher turn ratios and other coil mods are of no advantage and arguably a detriment in this application.
They can be useful at high rpm, high load where dwell time limited.
Higher voltage is mostly marketing phewey.
The voltage required to jump the spark gap depends on the cobustion chamber conditions and the gap distance. The fact that a coil may be able to produce a higher voltage would only help if there is a problem initiating spark. Maybe more important in general driving is the ability to continue to provide spark energy long enough to develop a nice kernal of flame. After that, the flame development is going grow on its own.