Consistency of the 'charge' value after simulation
When simulating with simulations.ObservedBound and setting the charge to a constant value (like 2), the "charge" value of the resulting CosmicRaysSets is only the set integer. When using a setup of multiple charges (like "mixed"), the "charge" value is an array containing the individual charge of each cosmic ray. I think it would be better if the output was consistent (always the individual value of each cosmic ray) so that the same code can work when only changing the charge composition without the need to check the type of the "charge" value each time.