If I double up in the first hand I play lvl 1-2 as if I had a T800 stack. You don't have a big advantance in the first levels (You don't bust as easily of course) - or atleast I'm not exploiting it. I just sit back and wait for good hands. In lvl 3 and up you can put pressure on the other stacks.

To sum up: There is no need to get more aggressive and fancy than you would be with a T800 (T1000) stack.