I agree with Ted.
I have used the .019 pad stack with excellent success.  Dog bone at .008 min
and direct hit to plane & .0275 clearance.  4n4 (.005 bonus for fabricator).
External row route only on BGA side.  Tent vias and if possible don't use as
test points.  I have used this on 13 x13 +inch boards that are .100 thick, no
sequential lam or microVia.
You will have aspect ratio of >7.5/1 so select a supplier that can perform.
Allow tangency not breakout.

Boston Brad

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