Some examples of offset, fractional length and heights.

Offset belts are straightforward. Place a straight belt diagonally (pressing R). You can use the dots from offset belts to make belts of different lengths. Combining those you can make them with relatively arbitrary length (up to 1.8? it will paste). The 2 length one has 3 dots and is just to show power pole.

Lastly, you can make fractional heights by letting a belt cross over another belt normally. If you can click on the belt dot above and drag down, it will move up the lower belt dot halfway... The 0.25 height can connect to a 0 height at 2 and 3 distance; the 0.5 height can connect with sorter to a 0 height at 3 distance.

Copy pasting these combinations will give you infinitely many options!