Uh, I think you have me confused with someone else. I agree completely with you. Kagan was far more dangerous. FAR FAR more dangerous, for exactly the reasons you mention.
Both you and Ninofan are correct. Everyone has to keep in mind that ALL of the candidates “the one” was considering were hardcore leftists and judicial activists; They are all extremely likely to vote in lockstep with the liberals on controversial cases and issues of import to conservatives;
That being said, Sotomayor was the “least bad” choice. LIBERALS think she is both intellectually and temperamentally unsuited for the Supreme Court. As such, I think the odds are that she will therefore likely have less influence in swaying Justice Kennedy (or any potential future swing Justice) than a smarter, more personable liberal activist (ala the late Justice William Brennan) would have.
Given the current political dynamics at play, a less persuasive liberal judicial activist is probably the best we can hope for from this President and Senate....