I'm not entirely Sure how to Answer this one, But I would imagine that your Killstreak Preferences would Match your 'Style' Sort of. For example, If your a 'Stick to the outside of the Map; Stealthy' Kind of Gamer, Then I would Suggest more 'Defensive' Style Killstreaks. i.e Spyplane, Mortar Strike, Black Bird. However the Same Applies for an 'Aggressive' Style Gamer. EG. Napalm, Chopper Gunner, Dogs.
See what I mean By choosing Your Killstreaks to suit your 'Style'. Defensive = Slower Paced More 'Strategy' Aggresive = Faster Paced More Shoot Anything that moves Total Anarchy.
However This May not apply to some people, Like me for Instance (When I DID Actually Play BO). My Style of gameplay would Depend on the Map and What Weapons I was Gonna Use.
So I don't think the Question 'What Killtreaks Should I use?' really Applies. I think A Better Suited Question would Be 'What Style Of Gamer Am I?'.
But Hey, Don't Just Take My Advise. What I said May Not Neccessarily Apply to this Situation; I just Wanted My 'Two Cents'.
But Just For The Sake Of Answering A Question Here Are My (Average) Killstreaks.
(Please Don't Hate I am Super N00B at BO)
Spy Plane.
Blackbird.
Dogs.
^^ I like to Know Where People Are so I Can Choose my Route through the Map.