I recently finished 4th in a daily tournament using this deck http://www.urban-rivals.com/presets/?id_preset=2296931
I finished with 496 points while the winner finished with 511.
Any changes i could make to perhaps gain more points or is it just hard luck?
No that deck is a winning combination. The only thing you were missing is some luck.
For instance, if you were to play a couple of terrible or very obvious players in a row and got KO + 1 pill left, you get about 120 points in 4 games (8-10 minutes) then you will likely win the DT. But getting into those fights is all luck.
Possibly Dayton -> Valentina if you have her, but you've done better than I ever have anyway