Everyone booked on a package must have the same components -- length of stay, length of ticket and dining (if included). Your best option is to book a room-only and then buy tickets for each person based on what they need. If you want the Visa financing offer for the room part, you can book it as a "ticketless package" as mentioned above. But the tickets (which are probably the largest part of your expense) will not qualify.
You could buy the minimum length ticket for everyone, and then upgrade those who need longer once you arrive. The challenges with this option include not being able to buy/book LLMP/LLSP in advance for the full vacation, and there is a the (slight) risk of not being able to add-on for your dates during spring break.
Also with budgeting be aware of the "extra adult" charge if more than 2 people over age 18 are in a room. The cost will vary depending on which resort but it can add up quickly over a week.