Probably neither of these two additional parameters are needed. Instead of introducing acceptNoDaughters, it is probably sufficient to replace
```C++
if( aParticle.numberOfDaughters() > 0 && isAParton ) {
```
with
```C++
if( aParticle.numberOfDaughters() >= 0 && isAParton ) {
```
Also, skipping a fixed number of particles in the list only makes sense for Pythia6, and in that case it has to be 6. So there is no need to make it configurable.

More generally, this is now a legacy code so it only makes sense to fix it to the extent that it gives the same result with the pruned GenParticle collection as with the full GenParticle collection, assuming all relevant partons are still present.