Oh-ho-ho-ho... SWEET! Four evolutions! It's kind of pathetic that this very nearly made my day...
OK, well...
First, I simply NEED to gain SOME control. I shall evolve a fin, to help stabilize my incredible movement.
I shall evolve a basic nucleus.
Also, I think I'll evolve a smelling sense (chemical receptors? Whatever you have listed on your index of evolutions that increases the smelling sense the most).
And, finally, I shall adapt a primitive feeding hole, which digests externally (stab prey with my needle and keep them stuck, spray abrasive cells (like a more primitive form of enzymes) on a concentrated area of my prey and "drink" the fluid that results (sounds somewhat advanced but was actually the most basic form of feeding on another animal).
[EDIT] Also, if it's allowed, please de-evolve anything that may be on my cell that has to do with filter feeding, or doesn't serve to achieve the goals of speed, control, or hunting. It's really just deadweight at this point.
Oh, and for my actions... just kill stuff.
Cheers!