Is it possible to make the API "sendRawPdu" a part of the next OS update?

Remember that this forum is community-driven so it is very unlikely that you get an official answer from the FP-team.

As we don’t know much about future FP OSs I can just forward you to this (unofficial) possibility of solving your problem: Cyanogenmod 11 for Fairphone FP1(U) Install guide + experiences.

But be careful as CM11 is probably affected by the Shellshock issue.