#3
The whole giving out tabs for free thing isn't good with the law. Selling those tabs would probably be illegal.
..I was watching my death.
#5
I definitely think tabs in general (whether it be from MySongBook or "official" sheet music, or amateurs) lack a ton in finesse and that quite few transcribers are really good.

To make full tabs (all instruments with great accuracy) takes a lot of time, one can spend a full work week to make such tabs. And I do think the result is worth paying for.

I've had a software idea for some time including full tabs with additional master tracks, the problem is the licensing.