[Heron]

I've little to none experience with 7 Card Stud but I just read a book about it and hence I have opinions about your play in this hand.

3rd street:

If you want to play your three very live high cards you should raise trying to knock some opponents out.

5th street:

Raising with your straight against QQ, 88 and 66 is of course the right play.

6th street:

Calling against 666 and 88 is OK.

7th street:

Here you could think about saving the last bet. Calling the 666 is OK but villain's raise means that he can beat far more than that. You can at best beat one of these guys.