Two good points from the always-thoughtful (even when I don't agree with him) Ramesh Ponnuru:
Her split-the-difference, compromising jurisprudence may have been designed to promote social peace, but if so it backfired. In two ways, it made the politics of Supreme Court confirmations more bitter. First, it tended to inflate the role of the Supreme Court in American life. When the Court sets itself up as a micromanager of policy decisions and provides no clear guidance as to what passes "constitutional" muster and what doesn't, the stakes in any confirmation get higher. Second, her career on the Court--along with those of Justices Kennedy, Souter, and to a lesser extent Stevens--made the Right suspicious of nominees whose loyalty to conservative principles had not been explicitly demonstrated. Conservatives learned that nominees often drifted left, and almost never drifted right, and adjusted their demands accordingly. It may not be the legacy she wanted, but it's the one she's left.
I disagree that her jurisprudence made Supreme Court nominations more bitter, but I do agree that conservative requirements for a justice's conservative bona fides is much more of a factor today AND that her incrementalist and case-by-case approach rendered the Supreme Court more important than it should be because instead of settling large constitutional questions once and for all, it settled them in particular circumstances thereby letting the lower courts and potential litigants know that certain facts could swing the decision in the complete opposite direction. That is especially her legacy on religion cases.