Are there any cases out there that extend Lagrone beyond future danger. I mean, if a defendant submits to a psychologist for "mitigation" in murder trial, logically he has waived the 5th to that extent. Right?

Here is a great case that you cannot cite, TRAP 77.3:

Ward v. State, No. AP-74695, 2007 WL 1492080 (Tex. Crim. App. May 23, 2007) (9-0) (not designated for publication) ("The appellant here argues that Lagrone applies only to cases in which the defendant attempts to present testimony on the specific issue of future dangerousness, and not to cases such as his, in which the expert will testify as to mitigating factors. We are not persuaded that Lagrone is so limited.").

Ward suggests this was all settled in Chamberlain v. State, 998 S.W.2d 230 (Tex. Crim. App. 1999) ("The holdings of Soria and Lagrone are governed by the principle that if a defendant breaks his silence to speak to his own psychiatric expert and introduces that testimony which is based on such interview, he has constructively taken the stand and waived his fifth amendment right to refuse to submit to the state's psychiatric experts. The focus is the defendant's choice to break his silence.").

The language in Soria and Lagrone does not seem to limit the application to future dangerousness.