(1) SSTB is clearly defined under §1.199A-5. The category that may require a little bit of interpretation would be the ones involving the reputation or skill of one or more of its employees or owners but even that is quite clearly illustrated in the examples. What interpretation are you looking for?
(2) Taxable income is what it is. For clarity, it is codified under §199A(e)(1) to not include QBID. There is really no room for interpretation.
Still an AllStar