Can of worms = Opened!!

I'll leave question #1 & #2 to others more experienced, but I'll have a crack at #2
Unfortunately, there is no correct answer to this question.
Saying something is the best sounding guitar is purely subjective, and no two people are going to agree on everything.
You could have two guitars built to the same dimensions with the highest quality spruce top, and maybe some Brazilian Rosewood for the back and sides, but the internal bracing is completely different, and they will each be loved by 49.5% of the people you talk to. The last 1% will believe you should have used Red Cedar for the top, and Hawaiian Koa for the back and sides, and a different bracing structure!!!
Take the same Spruce/BRW combo, and then apply it to a 0/00/000/Dreadnought or Jumbo sized guitar, and each will give you a different sound quality, and no-one will agree 100% on which is the best.
If you start throwing in other variables such as Cutaways(All the traditionalists start to shudder), or nylon vs steel strings etc. it just starts getting to hard.
Bottom line, The best sound comes down to your personal preference.
Some woods have a warm bassier tone, while others are brighter and give more of the treble end.
Skilled Luthiers can take all of that out of the equation by the way they construct the guitar.
A client could ask for particular timbers, but want it to sound like Martin designed in the 1940's, and just by "voicing" the internal bracing a certain way, they can accomplish this pretty closely.
Hopefully I haven't confused the issue too much for you!