Dear Ahm
Following is my suggestion for your plan:
(1) Enter the material planned standard price in MM as Material Price (MM03)
Why this is required through planned price? Whether your valuation variant requires this? If not then you should give prices through MR21.
(8) Confirming activities on Sep 8th once actual are there (CO15)
Confirm the activities at the time of order confirmations and later on calculate actual price for activity and revalue your orders on 8th Sept.
(9) Perform Goods issues,Goods Receipts, and Transfer (MIGO,MIRO) on Sep 8th
Do above activities on actual dates.
Rest seems to be OK
Regards
Rajneesh Saxena