Looking at the pictures, I was wondering if the outboard tip of the right side elevator centerline might be a bit above the stabilizer centerline?
Improved line tension will fix a lot of things. Not meaning more,
but more consistent.
Is there 1 >1.5 degrees or so of out-thrust in the engine? That would help, IMO. When the lines go slack, they get tight again much quicker. You'll need to adjust LO guide forward slightly to get the plane tracking tangent again. You do have adjustable LO's, right?