What is the impact if we separate out the instance of ETL (Work and Master) schema and Report Datawarehouse schema just like that of Portal content store. Rather than creating all three schema's in same DB, reason for question is I believe ETL Master will be comparatively a static DB, and ETL work will be pretty much build objects load to DW and destroy objects. Not sure how the procedures/triggers for ETL are build do we have them hardcoded based on instance we create?
The main issue is the disk the tablespace files are on. ideally they should be on separate disks, or san.