If the roach is "luffing" on all points of sail/trim, then I suspect you're missing some, or all, of your battens.
The suggestions above about topping lift are good ones. When you've really cranked the mainsheet in for close-hauled, the topping lift should still be a couple of inches slack. It really serves only to keep the boom from cracking someone's head, or your cockpit
seats/sole, when you drop the main.
Try these two things, and let us know. A couple of missing slugs shouldn't make much difference short term. And if the foot of the sail doesn't have a lot of vertical "I'm too slack" wrinkles, then the tension is probably all right, regardless of how far from boom-end the clew is.