Bloodlines
I am using Bloodlines in my world building to create variant humans. I think the write up in UA is one of the few real problems with the book. It doesn't make it clear if Bloodline levels are levels at all except that they apply to abilities that use class level as a numeric variable. I *think* the intent was that Bloodline levels would count as character levels, giving you the bonus feat and ability increase due at the appropriate level and giving you the Bloodline special abilities of that level.
For instance, a 7th level fighter with two Bloodline levels in a Major Bloodline is actually a 9th level character and receives the bonus feat for 9th level, the ability increase for 8th level and all the Bloodline special abilities for 1st through 9th level (I really wish they would have given an example character for this one, this is just my method). I think if you do it this way, it's a lot better balanced. The character is behind on HP, Base Saves, and BAB, but they have a lot more special abilities/feats/higher caster level to make up for it.
I'm also going to be using the Flaws too, but I think the Flaws in the last couple of Dragon Magazines have been a lot better than the ones in UA.