You may need to create a plane in the direction you want to pattern in order to get the pattern offset for which you are looking.
Did you try selecting both the dimensions that need to be used in the pattern? You can use the CTRL button and select multiple dimensions.
I would suggest a plane perpendicular to the pattern direction and a relation using trig to set the offset based on the diameter and angle.
Given the shape of the piece that you are trying to pattern, I am not sure that you can get a tight nest of parts. If you are offsetting one thickness on the top of the shape, that will not give you one thickness on the ends. But if you offset one thickness on the ends, you will have a gap at the top.