I'm not so sure that the stock pickup is at fault for being a little weak on the high E string. That string is so light that it moves the electromagnetic field only slightly in relation to the other strings.
I turned my Mandobird into a Mandolabird and got great results from the stock pickup. Of course, now I need to move the whole bridge back a little to get the proper intonation on the C string.
Regarding the usefulness of a mandobird, I use it as much as possible. I think of it as a lead instrument, and almost never try to play rhythm on it.
Daniel
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