You'll find several threads I participated in urging that a structural ridge line be used with Clarks, even though you will have to attach it beyond the ends of the hammock (a total of 16+" ) in order for the line to clear the hoops. Unless Clark changed the sewing, I also think the default position is tighter than it would be for you to be more comfortable. All that is in earlier threads.
So, set up a structural ridge line and set it, at a start, for 83-85% of the maximum distance spanned. Or set up your NX-250 with the hoops AND with a a 3/4" tape measure in hand. When you have the hammock the way you think you like it, let the rods loose so the hoods collapse, and so you can measure the distance between ends as you sit in the hammock. I think that if you measure more than 92", the hammock will be more comfortable strung looser.
Tell us what you think.