Replaced the dual point with HEI

Great that your engine is running better. With all the changes, it is hard to know how much improvement the HEI part made. That it allows a larger spark gap always helps. It is also one less "knob" to adjust since dwell control is integral. The earliest electronic ignitions like ~1972 Mopar and even early after-market like Crane Cams XR700 still needed a ballast resistor (one more part to fail and more wiring) but still no dwell adjustment.

Even simpler is MPFI with crank-triggered ignition (~1987+) since no "knobs" to adjust. It is almost magical after rebuilding such engines when you just align the camshaft gears, connect the sensors and ECU and it fires up and runs perfectly, without having to adjust anything (nor can you) since all tuning is built into the computer, based on lab testing of the engine. If you modd'ed the engine (wilder camshaft) it may no longer be optimal. With aftermarket FI, you have many knobs to tweak (fuel and spark maps), which is very involved so auto-tuning as-you-drive software became common. Even with a factory ECU, some can hack the software to change it (tuners), but that requires expensive dyno time.