Oh...So maybe pre-made ships are allowed?

Oh, I guess that's what "-Constructing the vehicle outside the bounds of the VAB or Hangar" means. I assumed it was referring to mods that give you more space. But I guess that's redundant with the "no mods" rule.

In the stock game, you are able to position the ship so that parts of it stick out the roof of the VAB. One of my super big Eve missions had to do this. Any reason why that wouldn't be legal?

I'm of two minds about it - obviously it's something that the game directly supports. On the other hand, constructing the ship is a large chunk of the actual gameplay.

I recently did a challenge for "completing" career mode in the fewest number of launches. The definition of "complete" was the same as your 100% category but additionally to finish every progression milestone so that you no longer had any "world's first" contracts being offered. This includes things like docking ships on the surface and crew transfers in orbit around every body. The 100% category right now really isn't much different than the All Planets RTA category - what do you think about changing the rules to include the progression milestones?