The top with the “lines” comes from the fact that your shape is not flat and even if it is flat, it is not paralel to the print bed. So the printer creates multiple layers to cover this shape.
Se my pictures from slicer program, with a flat surface printed in diffrent positions. Note how the lines start to appear after an angle of only 1 degrees. Note also that on 90 degrees the big flat area is at it’s best, but the side is not so good. There is this technique that you use a big angle (but not 90 degrees) to have a very good finish on the surface that you are interested, yet still a quite good finish on the other surfaces, this corresponds to the 60 degrees angle from my pictures.
Hope this helps!