Super quiet audio recording in Quicktime 10.4 using Soundflower-2 on Yosemite
I'm not sure if you've tried this, but the more important one is the volume you have routed to soundflower. To achieve a similar volume coming out of your speakers and still getting a louder recording, you'll have to lower the output volume and raise soundflower's volume.

Also, I'm not sure about you but soundflowerbed works all right for me.