Electronic Ignition. If I'm going on a budget, the factory magnetic distributor is a good starting point, and then re-curve it for your engine combination, then use an HEI module on a heat sink (Cheap and simple.) I will use a chrysler type ECU if I need to, but they can sometimes be a problem as the case needs a good ground connection.
When I look for performance distributors, I look to see if they are easy to modify the advance curve. The Accel and Mallory distributors I had used used a "key" with different width / advance settings and you just loosen the advance screws, set the advance with the key and re-tighten the screws. The MSD uses a bushing stop that you replace.
I think it is easier to get replacement parts for the MSD, but they really jacked up the cost of those.
I haven't used Fire Core or Pertronix, so I don't know how they adjust the advance curve, but they seem to get good reviews.
On a Big Block, be careful with some of the bigger billet bodied distributors as they might hit some cylinder heads, and then you need to clearance the head for clearance.
Had to clearance a 440 source stealth head for a FAST dual-sync distributor for the sequential EFI setup.
Most of my cars use a CD Ignition box, with the square E-Core coils. The combination provides greater spark energy. As mentioned, peak output voltage is not the correct way to rate ignitions, spark duration and current is what you want, and all of those need to be balanced.
Need voltage to jump plug gap under cylinder pressure. More pressure and larger gaps take more voltage, but more voltage is also harder on the plug wires to contain.
Too much current can reduce plug and wire life.
Too long a duration can cause crossfire in the distributor cap. The "Multi Spark discharge" of CD boxes becomes a single discharge at higher RPM to prevent cross fire to the next cylinder. With the distributor, the ignition limitation is the cap to rotor geometry. That is why newer cars used multiple coils to get rid of the cap/rotor problem. The next smaller issue was long spark plug wires that cause electrical noise and the longer lengths added resistance to reduce noise, so now we have new cars with either coil near plug, or coil on plug.