Is this normal? No. Does sit warrant concern? Absolutely.
It is the pilot's responsibility to understand aircraft operation and to fly in a safe manner. You need to be evaluating all flight and especially those that don't go right. This...
What about the flight data from the flight log? Details matter. How far did it drift to the right? What were the wind conditions? When did it achieve best GPS connections?
Depends on the end use of the pic, or personal preference. As an architectural photographer, I probably correct my verticals over 95% of the time. My clients don't build buildings that are falling over, so they don't want photos that look like...
Check with your MLS provider. When listing on the MLS they have specific requirements as to what and how you list picture information which is not exact. If you are not listing with MLS they you just have to be truthful; otherwise and unhappy...