Re the cheap mics, the usb one is pretty good for recording my 'harps, as it so happens, (I think it cost £27), so not a total loss money wise. 
When recording videos, I was using guvcview, (it comes as part of my Linux distro), which does a pretty good job, when I remember to use the right input, as does audacity, when I record my 'harps, (which I am getting better at, but still a long way too go). 
I can certainly get a lot more volume from my ukes if I use a pick, but not comfortable with using one yet, or if I really want to.
Trying to do justice to various musical instruments.
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