Ballast

I would "get back" to a more street traditional setup. You can create a situation where the coil runs hot and fails, and you can have a situation where the ECU is switching too much current and fails

Additionally, I disagree with the idea of running a coil designed for no ballast. The reason is that these were designed originally so that during start, when battery voltage is lower, the ballast is bypassed to provide a hotter starting spark.