Is it the body or the lens?

Hi guys,
I am playing around a lot with my new EM-1 and the 14-150II to see if I will jump to the MFT format.
Today I was walking around in SF and took some shots. When I got home I was a bit dissapointed about the image quality that I got out the combo and I am wondering what the problem might have been (me included).
What I was especially disappointed about was the noise (at even 200 ISO), the lack of detail in the pics and the blur (I thought that I would be able to handhold this lens at 300mm with the IBIS).
Can you please help me a bit understand where the problem is or IF I am just expecting too much from the system?
Thanks!