Good points. I have an idea about managing samples more effectively.
The ability to flick through different samples placed on the same pad within Impact, and choose which one(s) you want to use. All the samples would be saved as a preset. You could resave as a new preset and delete the unused samples if necessary.
For example, I have a folder of 13 Alesis SR-16 kick samples. I can drag them all at once onto a pad in ImpactXT, and save this as a basic SR-16 preset. Then I'd like an added option in Layer Mode to play only the sample I've chosen from the top of Impact - above the sample window. To expand this, you could choose multiple samples at once.
Or perhaps more options are needed in the right click menu on those blocks above the sample window to "solo" or "mute" the selected samples. Then the layer mode would work on the chosen samples.
And keyboard shortcuts to step back and forward through the samples would be very handy.
In this way you could have the option of making your own presets to have a set of samples to choose from for each new song, instead of having to drag/drop from the browser every time.