It may well be that the supposed leak isn't legit, but I don't think any of those statements necessarily rule out the leak as being legit.
- The new protagonist will be somehow related to N7 - The protagonist could have been an N7 during the Reaper War. What if the characters of ME:Next are Reaper War survivors that were in cryo sleep during the journey to Andromeda?
- The new protagonist will be skilled but not an established hero like Shepard - Nothing in the leak says that the new protagonist would be an established hero. In any case wouldn't N7 status run counter to that statement anyway?
- The new story of the next Mass Effect will be much more personal than the Shepard trilogy - Whether or not a story is personal has little to do with where it is set
- It is very likely we will see familiar faces in the next Mass Effect - Familiar faces could end up aboard an ark ship. There is nothing to prevent some of the non-party NPCs from being Andromeda colonists.
- The Mako, an Alliance Navy vehicle, is making a return in a major way - If the Andromeda colonists are actual survivors of the Reaper War and not their descendants, they would be using imported Reaper War technology. We should expect them to be using the Mako as the ground combat/exploration vehicle. In any case the Mako concept we saw looked different than the familiar version from the Shepard trilogy.
- The next Mass Effect will not use Dragon Age: Inquisition as a template - This is the only one that perhaps works against the leak details, but I also don't think it rules it out entirely. After all in marketing speak it was also claimed that Dragon Age: Inquisition wouldn't have many of the flaws that it actually turned out to have
Let me further elaborate on these points and why they are a contradiction.
1. The entire survey is based on the premise of the Ark theory. In other words, the Arkcon Pathfinder Initiative that BioWare Montreal teased in a tweet. We have no reason or evidence to suggest this is in any way affiliated with N7, let alone the Alliance Navy. Yet, the entire survey is built on the premise that you are a "patfinder," which appears to be an explorer and not a soldier. Thus, it's unlikely what we know from BioWare about the protagonist can also be true about what the survey suggests about the protagonist.
2. BioWare seemed to describe the new protagonist as a N7 recruit, similar to James Vega. He/She doesn't have a reputation yet, but has gotten far enough along to have been invited into an elite organization. Again, BioWare's explanation bears heavy weight that we seem to be going towards another military/soldier-esque story. The survey in no way supports that evidence.
3. You missed the point here. The new "story" in the survey is another conflict of galactic proportions with humanity on the line and the protagonist has to save it. What BioWare has described is we will not have another "Shepard story" and this will be much more intimate and building relationships with your crew. Again, more reason to believe this survey is fan-made.
4. Who exactly would constitute as a "familiar face" we could see outside the main party? Many of the side characters established throughout the trilogy died in ME3 in one way or another. I'm fairly certain BioWare was alluding to previous party members, similar to how Leliana and Morrigan are featured in DAI. Thus, jumping to another galaxy doesn't make a whole lot of sense when they obviously wouldn't be present on this "Ark."
5. My point is that the Mako is an Alliance Navy vehicle. Whereas the Ark theory and this survey are premised on the "Arkcon Pathfinder Initiative," which seems to be an entirely independent organization dedicated to exploration. Why would they have military-grade technology? Again, going back to the fact the main protagonist is using N7 armor and a heavily modified and advanced Mako, it's likely he/she is a soldier and not an explorer.
6. Mass Effect doesn't need to copy Dragon Age Inquisition. For one, DAI's open world exploration was largely a disappointment with grindy, MMO tendencies. It's clear bringing back the Mako and this focus on exploration is largely being drawn from ME1. Again, I doubt we will see much parallel between NME and DAI, if anything.
I stand by my initial statement that the likelihood of this survey being true is less than 1%. It just does not corroborate with what BioWare has told us about this game.