So you do wan't to use the excisting Kits. But the idea of the Kits is it's designed Kits. Kits can use the same base sounds, where the difference perhaps only is in the use of effects.
You can design Kits your self, that does'nt have any effects added. But apparantly you don't wan't to use the time to do this.
If a drum sound is a sample and the sample include sampled effects, then you can't remove those effects.
But in the Mixer you can remove the master effects quite fast. Many Kit's Reverb come from here. So it would take a couple of seconds to remove that reverb.
If an effect is added to a single sound, then you need to edit that sound separately in the Mixer or Studio section. You apparantly don't wan't to use the time for this either. I can't see it should take more than a minute to remove all effects in the Mixer view though.
When a drum sound is a sample, then you can load any dry sample directly into a layer in the sampler in Studio view.
Keep in mind, that sounds also can be made is the Modular module, so it does'nt have to have any samples in it.
The instrument you edit will allways be the one you have selected. So if you press a pad or the instruments in the sides of the studio view, then you work on the sound for that pad. (Keep in mind, that if you load a sound in the side drop down menus or use the Library Instruments, then they will have effects added, if it have any effects.). Only in the sample in the center will load dry samples. But it will have the effects that's allready excist, unless they effects are not removed for the pad. And again keep in mind that you also can create sounds without samples in the Modular.