I frankly do not know if the target class is bigger for engineering. Art and Science is definitely looking for more students. Part of the reason for larger number of acceptances in engineering might be because more of them are to out-of-state students this year, where the yields are expected to be much smaller (especially if it is more out-of-state students without national buckeye scholarship).
Good luck to you! Have you been admitted to OSU (on explorations?) and waitlisted for Engineering (I don’t know if they actually do that!) or are you waitlisted for University admissions. If the latter, I suspect that you best case scenario might be admission into Explorations, I am sorry for say!