Hi Jed,
I agree with Dennis regarding the Streak-1&2 wings. If you're not off the ground after 200 metres, even at MTOW, ie, with passenger & full jerrys in your paniers, then there's really something wrong, even on grass.
Though depending on the approaches to your strip you might want to get at least 50hrs/150 landings under your belt before using it if it's not ideal. Then you should be able to get off the grass at MTOW in still air within 150 metres and stop a with 50 metre skid mark - nose wheel braking only.
Cheers,
Glen