Sputnik if you can find the 631 version. Great package, and when bought used the value is high. I have said it before and will do so again: Spicer cycles are a good value if weight is not a huge concern.
Otherwise, try to find the best overall package based on usage. I would look at geometry you like (track, relaxed, etc), then pick frame that can fit at least 28c if not larger. As previously stated, frame up builds will never have the value that a premade bike has.
Pick something and ride it! Then let us know.