By pushing up the exposure a bit, the image was washed out and even after image processing, no more detail could be seen.
ISO 3200, 10s exposure and a few more frames.
The timer automatic shutter release is compatible with the new camera, so good!
BTW, this is done with my newly received early birthday gift which is a 70D! I never imagine that I will ever upgrade my camera, thanks to my sister.
Seems like I've reached the indoor limit with those light pollution.