Hi Otis. I have some educated opinions on this.
1. Over rev limitation. I agree.
2. Software vs. discrete logic. I agree in general, but at some point software will be embedded in everything. I am working on a new generation trim and flaps controller that works entirely in hardware, but when a CPU is plugged in, additional features are enabled. In this way, the software driven functions work in parallel with the hardware. Sort of like a 'limp home' mode. I think it's reasonable to ask all of the ignition/ecu vendors that use software if they support such a mode.
3. flywheel triggers gives precise, repeatable ignition timing events, whereas accessory case driven timing has gear lash so the ignition timing is 'dithered' around the ideal timing. This may not be a Bad Thing. Just ask the prop vendors about resonances and electronic ignitions. Dithering may reduce these resonances and is a common technique in electronic systems to reduce radiated emissions. Flywheel triggers have their own failure modes that can be nasty. I have had inflight failures with a flywheel system...Yikes!
There is another issue related to electronic ignitions that needs addressing. Many systems allow you to increase the spark gap on your plugs to provide a 'hotter' spark. This means that the spark plug wires operate at higher voltages and are subject to faster degradation and flash-over (misfire). Routing and separation of these wires is more important. I have found that careful gap control is important... make sure all plugs have the same gap and that the gap never exceeds the allowable specs. In fact, bigger is not necessarily better because modern ignitions have long duration lower voltage sparks, rather than short, high voltage sparks.
V