After a lot of testing for corner counter hit s.C+D follow ups, these seem to be the most reliable and consistent... If the first qcf+A connects then the rest will always work no matter the range... Also in the corner s.C+D, qcf+A can't be jumped out of... If they try to jump it then they will get hit and Mai can link s.D into an HD combo...
s.C+D, qcf+A, qcb+A, qcb+C, qcb+C, air throw = 450 dmg (0 meter)
s.C+D, qcf+A, qcb+A, qcb+C, qcb+C, qcb+C, DC, qcf+A, qcb+C, air throw = 541 dmg (0 meter + 1 drive)
s.C+D, qcf+A, qcf+A, qcf+AC, qcb+C, qcb+C, qcb+C, DC, qcf+A, qcb+C, air throw = 612 dmg (1 meter + 1 drive)