(see full development and annotations in flip file)
I have chosen to develop logos 3, 4 and 6.
Logo 3: I chose to develop this as a logo for a garden centre/nature park due to the natural elements, the bird and the leaf. I wanted to retain these elements to keep the logo relating to its purpose, but make the bird look more like a bird, and maybe incorporate a flower, and experiment with colour.

I think I have made the logo more fluid (the bird looking like it is in flight) and successfully made the bird imagery more apparent. I chose the bright colours to make the logo stand out, but also to create an exotic feel (relating to birds and plants).
Logo 4: I chose to develop this as a logo for a sports team, perhaps for a popular American sport due to the 'stars and stripes' imagery already included. I wanted to take the opportunity to experiment with using the round element (the letter D?) as a ball, preferably red, with the 'F' blue so as to use colours of the American flag.

After having experimented with an American football as the 'D' (with the distinctive stitching in white), I chose to use a basketball as it was a more accurate shape. The 'swoosh' on the 'F' was intended to make the logo look as if it is rising up, emulating a basketball player jumping up or throwing the ball to score (creating movement, another link to sport).
Logo 6: I found developing this logo the most difficult. I chose to develop it as a logo for a wool/textile company because of its interweaving lines. I wanted to retain this effect but re-arrange the elements so that they no longer resembled the 'S' shape.

I am not entirely pleased with this outcome as I do not believe I retained the interwoven quality very well, however, I think that the thin curved element I added works well as it resembles a fibre of the wool/thread.