The best way is not to create the data in the DS. Use association, before coming to the page- create objects , set it to association and retrieve here through association. Add helper entity if needed.
This could be the best way.
Hope this helps!
In your datagrid, enable Refresh time in seconds option which is available in datagrid.
disable the refresh in client in delete object activity in your delete action microflow.
So Once you click delete button object will be deleted, When your datagrid is getting refreshed for every 1 sec, you can see the deleted entry which is getting removed