Please move mod settings from Startup tab to Map tab.
It will be much better and more useful, when you can change the setting whenever needed.
Also you can add a tool, like Shovel in shortcuts menu, that will remove all corpses in the vicinity of the player when used.

Moving the fading options from startup settings to map settings is impossible as the fading times are set in the prototype stage which is only done on startup, hence it is a startup setting.

I won't add a tool to this supremely simple and stable mod. Aside from performance and compatibility considerations a tool like that simply does not fit in the style of this mod.

Corpses already fade away over time so why not just await their eventual disappearance? Does it take too long well then simply make the fading time shorter.

There is a different mod that gives you a lawnmower tool which removes all terrain features, including biters and tree stumps but I am not sure about destroyed buildings.