To me it all seems remarkably simple:
1. I think that a person being nominated for a life time position for one of the most influential positions in the USA should be vetted very carefully.
2. I believe that Dr. Ford sincerely believes that Kavanaugh attacked her sexually when at school and that her account is sufficiently plausible (even if by no means proven) that a further, truly honest investigation of this accusation is essential before a final vote on the nomination. This guy is going to make major decisions that will affect the country and its people for decades; delaying a vote even a few weeks is a minor issue compared to the possibility of placing an attempted rapist on the highest court in the land. It is only reasonable. Not doing so for political expediency would be outrageous.
3. Kavanaugh denies he is guilty. Sure, that is possible too. So he very much deserves an investigation to clear his name. Frankly I cannot understand why he would want to be confirmed without being given this opportunity, which appears to have been the course he and the Republican leadership favored until their last minute U-turn on Friday. Being outraged is not a substitute for clearing one's reputation.
4. Separate from the sexual assault accusation, Kavanaugh has repeatedly demonstrated his willingness to lie and dissemble under oath. His behavior in the committee hearings on Thursday not only confirmed this but further demonstrated that his temperament, political bias, and paranoia render him completely inappropriate for the high court.