Because your data was sampled from a real-world object, it might be good to use that data directly.
You have to create the object as it was intended, and not as it was build. If you start out with “random” lines, what you end up with likely will not come out good.
So, you can draw curves which describe the ends and outlines of your part.
By looking at your part long enough, or feeling it in your hands, you can tell that one end is round, and the other end is square but with rounded corners.
Then your part more or less follows are curved path, so you need curves which describe sides, OR the center line of the flow, as water would pass through a thin pipe.
We can also see that you part has thickness like a pipe, that will have to be drawn too.
For the outside, there are at least 3 ways to make it.
1.) As @ec2638, wrote, by using the ovals you have on either end, and one or two good curves that guild the sweep, you should get a nice shape.
2.) You can also add a few more cross-section rings and use the loft command.
3.) You can made some side curves and use the curve network.
At times, it can seem hard to learn how to attack a part, but after a while, you will be looking at everything in your house, and seeing how you can make it. Then you will see what has not been made yet…