The first two would be minor corrections. The latter two would naturally require more attention and detail, but they don't apply to most people.
> Deducting mortgage interest?
The IRS has my 1098s. They know the mortgage interest, principal, and origination date.
But they don't know what you used the proceeds for. Not all mortgage interest is deductible. Nor do they know what use you make of the property that secures the mortgage (primary residence, rental, other). They also don't know about prior year points you paid to originate a mortgage.
You failed to address this important point. There is a difference between acquisition debt and equity debt that the IRS has no information about your situation. Also the "primary residence address" is not required to be provided on the tax return, so no they can't "reasonably assume".