consideration when object removed

Hi all,

I would like to delete certain objects from the Existing Universe and also the columns from the Database Tables used by those objects as well. I am following below process.. Please let me know if i am missing anything.

1. Find the objects

2. Find out the columns Used by those Objects

3. Check the these columns used in  select/where clause of the other objects

4.Check the object to be deleted called in other objects by using @select

Also few more questions

1.what happens when you move a object from once class to other class ?

2.What happens when you remove a object from universe which is used by a report ?

3. What happens when you remove a column which is using by report object from the database table ?

Thanks in advance for your help

Thanks,
Srinivas