@Diogenes08 I moved your post to a new topic. It does deserve it’s own .
I guess you mean that selecting different engines like fluidsynth, black pearl, etc or banks within an engine like fluidsynth’s standard, power, etc. have the same drum on different notes or that they have the same mapping but fewer sounds. This is true because there isn’t really a standard mapping for percussion sounds. The General MIDI spec does list a drum map so a preset within a GM instrument should follow this but anything else is free to do what they want. Some may have fewer sounds but map them over the GM map. Some may follow a TR808 map. Some may have several variations of the same sound, e.g. snare.
There is a mechanism for presenting names of percussion instruments mapped to MIDI notes called MIDNAM. The step sequencer uses this to show the drum map in the pattern editor.
I think you may be suggesting a mechanism to map certain keys to the same type of sound in each instrument. Due to the complexities described above this may be challenging. Your preference for a kick drum sound from an engine may differ from the next person.
We are to a large extent constrained by the upstream developer’s choices. I can see there could be a mechanism for mapping notes to instruments but am not sure whether the benefit outweighs the effort to implement and complexity to configure and maintain.
If you have a genius suggestion then please share it. We do love to hear how we can improve the Zynthian.