How ribs angle change wing overall shape?
It depends on the rigidity of the upper and lower skins.
As far as large jets go, you see different variations; ribs parallel to the airflow, ribs perpendicular to one of the spars, ribs perpendicular to mean chord.  In the 737 cutaway below, they appear to be more or less perpendicular to the rear spar.
Aerodynamically it's not important on large swept wing aircraft, since the ribs' orientation doesn't impact the outer contour of the airfoil, because the upper and lower skins are very heavy and stiff and are effectively the spar caps (the primary tension and compression members of a box beam), and the &quot;spars&quot; are really just bulkheads closing the box at the front and back, with the ribs supporting the box. So whether you angle the rib this way or that doesn't make much difference and it comes mostly down to ease of manufacture.
On the other hand, if you have a swept fabric covered wing, or a metal wing with thin skins that can bulge between the ribs, then it could be an issue and ideally you'd want the ribs to be parallel to the local air stream (which may vary a bit from the free stream) as much as possible to minimize air flow &quot;across the bulges&quot; so to speak.  But if the upper and lower skins are stiff enough to retain their contour between the ribs, it makes no difference and you can orient the ribs in a way that makes it easiest to build the wing, with the rib contour shaped to accommodate the orientation in achieving the overall airfoil shape.