Exactly right about the kill-streaks. The best combo imo is the one you mentioned, Pred, Harr, Pave low.
I have been playing mostly Free For All which, you really have to play mostly defensively on. Although, for certain maps, being offensive is key because people like to camp in FFA. Now whenever I play other game types, Dom, Sab, etc, I play well because I am so used to being able to play both def and off. My KTD reflects my tactics as right now I am at 1.95 pushing for two this week.