I just noticed, that if i delete something (mostly by accident) and then try to redo (ctrl-z) that element i deleted, although appears back, has all its editable settings (like spinning speed) resetted to its default. 
I don't think this is desired behaviour.
After all when i hit "redo" it means that i changed my mind and want given element back on (or off, but in such case there would be no such problem).
Necessity to set its keybinds and parameters again is quite pain in the ass (especially if there will be blocks with more customizations).

I guess it shouldn't be very hard to implement (at least not as "totally-different-mechanics" hard)