Can you clarify "loading in SM"? Are you expereincing a long delay in just sending a BVR to SM or are you doing something else like "expand below", loading JT graphics, or launching to NX.
There are standard DB things that would help performance like checking for missing indexes, and regenerating Cost Based Statistics in Oracle, etc. and increaseing the RAC Xmx memory also helps with large BVR structures.
"Sending BVR to SM" use case is of higher priority but not limited only to this use case. All use cases where business users struggle while working with large assemblies in Teamcenter can be considered, not limited Structure Manager only. JT and CAD files can be ignored.
Since this is RAC based performance stuff I would suggest you look at standard performance optimization stuff for DB, RAC, etc. to make sure TC is operating at full capacity. I can send you the latest perfromance olptimization tdoc's if you'd like. You can also look into Journal Workbench to see if you can identify any anonolies in the "Send To" action; otherwise I am not aware of any SM Best Practices like NX has using "Lightweight Representations".
NX 11 | SW 2016 | Creo 4 | TcUA 11.4
Evaluating: AW 3.4