I have to vote with teflonrock on this one, leave the streamer off the booster unless you absolutely MUST use a deployable recovery system.
Booster tumble recovery works just fine. It is simple, cheap, light, reliable, etc etc. About the only time it goes wrong is when you launch from a paved surface like a parking lot (DUH!) and the booster gets dinged when it lands, but you will get the same damage if it lands there under a streamer or parachute.
Anyway, there is almost always a way to make a booster tumble, but if the balance won't work out you could make it break apart. When I was a kid, I saw a rocket with a break-up booster that worked really cool. The booster stage had left and right halves, with the BT split down the middle (I think each half had two fins attached). The motor tube was attached to one side only. The two halves were held together with some kind of ring at the very bottom (the ring was part of one of the halves) and the upper stage slipped over the front and held it together. When the thing staged, the two halves split apart and tumbled down (I think they were tethered together).
And to stop the wadding/recovery from sliding aft inside of long BTs, I remember a reader suggestion from one of the old rocketry magazines (Estes newsletter?). Using a short length (1/4 inch or so) of splice or joint material, glue some balsa or spruce strips inside the tube in a 'criss-cross' pattern, leaving most of the tube open. Add fillets, and coat the exposed wood with epoxy. Slide this assembly inside the front of your BT, down to where you want the bottom of your wadding/recovery materials to stay, and glue it into place. This will hold everything in a forward position while under launch acceleration, and still let the ejection gasses through to finish the flight.