I think that'S the best way to go with instead of radio buttons, as of matter of fact, I already made the cosmetic changes.
Now, I have added the three new columns and my "total hours per day" formula is now on O10 - O25 which is here
=IF(I10<H10,I10+1-H10,I10-H10)+IF(K10<J10,K10+1-K10,K10-J10)...