Simple to fix those ribs.  First get some 3 by 5 card stock and put next to the good rib.  Carve off those gobs of glue on the LE and fit your car stock in, then trace the front of the rib.

Cut some 1/2 ribs out of the appropriate width of balsa.  Use these to replace the badly cracked or broken ribs.  I recommend sawing off the old rib about 1/2" out from the spar and gluing the replacement to this and the leading edge.

Voila,  Strong and light.  Looks fine.

Tom