Hi Arturo,
I many not be able to answer your question. However, i would like to share my experiences.
I have recently been in a project where the client was using HANA Side car.
Case : There was a cycle that was having more than 600 segment and the Database selection was nearly 38 min (despite being on HANA).
We have used allocation Structure and PA Transfer Structure and reduced the cycle to 16 segments the database selection time was reduced to 0:30 seconds.
You might have already thought of it, but in case you did not, i suggest you to use allocation Structure and PA transfer structure. unless you have a separate ratio for each cost element posted to your cost center.
Before i end this...i would like to thank you for your services to the community and people like me
Thanks & Regards
Surya