I think we are missing the point of pregens. They are really to allow a new player a chance to play without going through the task of character making and to avoid overloading them with a lot of rules. The high level ones are just a bonus to current players to allow them a chance to play the higher tiers when they have yet to get a character to that level.
They aren't supposed to be these amazing munchkins who tear up a scenario on their own. They are a taste of the game, or simply a substitute in the case of a current player.
Also nothing is stopping you from making a level 1 barbarian and handing it out to new players. Just write it up and hand it out. If the player doesn't like it they can change it according to the rewrite rules. The same goes for any of the base classes. Just keep it simple and stick to core book content. Same goes for any other class in the game. Just be ready to do some explaining if you are handing out a Magus, Samurai, Oracle, or etc and stick to stuff from only their book plus the core.
If you find out your created character goes over well with new players then feel free to post it for others to use.