For people who are concerned about spoilers, the Backer Beta will feature a number of areas near the middle of the game that do not have strong connections (if any) to the critical path. In addition to the characters you create, we are also likely to feature a roster of pre-made characters who are not companions. We don't have any interest in using the Backer Beta to give out story info. We'd much rather have people play it and throttle the mechanics, UI, etc. so we can make fixes and adjustments.
Will we be able to level up the characters to the max level? Not that it's important to me personally, but more as a way for you guys to get feedback from q&a testers and backers.